Bug 927765 - Options for createObjectIn. r=bholley

js/xpconnect/src/Sandbox.cpp

@@ -1253,13 +1253,16 @@ GetExpandedPrincipal(JSContext *cx, HandleObject arrayObj, nsIExpandedPrincipal
  * Helper that tries to get a property form the options object.
  */
 bool
-OptionsBase::ParseValue(const char *name, MutableHandleValue prop, bool *found)
+OptionsBase::ParseValue(const char *name, MutableHandleValue prop, bool *aFound)
 {
-    MOZ_ASSERT(found);
-    bool ok = JS_HasProperty(mCx, mObject, name, found);
+    bool found;
+    bool ok = JS_HasProperty(mCx, mObject, name, &found);
     NS_ENSURE_TRUE(ok, false);
 
-    if (!*found)
+    if (aFound)
+        *aFound = found;
+
+    if (!found)
         return true;
 
     return JS_GetProperty(mCx, mObject, name, prop);
@@ -1336,6 +1339,23 @@ OptionsBase::ParseString(const char *name, nsCString &prop)
     return true;
 }
 
+/*
+ * Helper that tries to get jsid property form the options object.
+ */
+bool
+OptionsBase::ParseId(const char *name, MutableHandleId prop)
+{
+    RootedValue value(mCx);
+    bool found;
+    bool ok = ParseValue(name, &value, &found);
+    NS_ENSURE_TRUE(ok, false);
+
+    if (!found)
+        return true;
+
+    return JS_ValueToId(mCx, value, prop.address());
+}
+
 /*
  * Helper that tries to get a list of DOM constructors and other helpers from the options object.
  */
@@ -1369,7 +1389,6 @@ SandboxOptions::ParseGlobalProperties()
 bool
 SandboxOptions::Parse()
 {
-    bool found;
     return ParseObject("sandboxPrototype", &proto) &&
            ParseBoolean("wantXrays", &wantXrays) &&
            ParseBoolean("wantComponents", &wantComponents) &&
@@ -1377,7 +1396,7 @@ SandboxOptions::Parse()
            ParseString("sandboxName", sandboxName) &&
            ParseObject("sameZoneAs", &sameZoneAs) &&
            ParseGlobalProperties() &&
-           ParseValue("metadata", &metadata, &found);
+           ParseValue("metadata", &metadata);
 }
 
 static nsresult

js/xpconnect/src/XPCComponents.cpp

@@ -3011,29 +3011,52 @@ nsXPCComponents_Utils::GetGlobalForObject(const Value& object,
 }
 
 /* jsval createObjectIn(in jsval vobj); */
-NS_IMETHODIMP
-nsXPCComponents_Utils::CreateObjectIn(const Value &vobj, JSContext *cx, Value *rval)
+bool
+xpc::CreateObjectIn(JSContext *cx, HandleValue vobj, CreateObjectOptions &options,
+                    MutableHandleValue rval)
 {
-    if (!cx)
-        return NS_ERROR_FAILURE;
+    if (!vobj.isObject()) {
+        JS_ReportError(cx, "Expected an object as the target scope");
+        return false;
+    }
 
-    // first argument must be an object
-    if (vobj.isPrimitive())
-        return NS_ERROR_XPC_BAD_CONVERT_JS;
-
-    RootedObject scope(cx, js::UncheckedUnwrap(&vobj.toObject()));
+    RootedObject scope(cx, js::CheckedUnwrap(&vobj.toObject()));
+    if (!scope) {
+        JS_ReportError(cx, "Permission denied to create object in the target scope");
+        return false;
+    }
     RootedObject obj(cx);
     {
         JSAutoCompartment ac(cx, scope);
         obj = JS_NewObject(cx, nullptr, nullptr, scope);
         if (!obj)
-            return NS_ERROR_FAILURE;
+            return false;
+
+        if (!JSID_IS_VOID(options.defineAs) &&
+            !JS_DefinePropertyById(cx, scope, options.defineAs, ObjectValue(*obj),
+                                       JS_PropertyStub, JS_StrictPropertyStub,
+                                       JSPROP_ENUMERATE))
+            return false;
     }
 
     if (!JS_WrapObject(cx, &obj))
+        return false;
+
+    rval.setObject(*obj);
+    return true;
+}
+
+/* jsval createObjectIn(in jsval vobj); */
+NS_IMETHODIMP
+nsXPCComponents_Utils::CreateObjectIn(const Value &vobj, JSContext *cx, Value *rval)
+{
+    CreateObjectOptions options;
+    RootedValue rvobj(cx, vobj);
+    RootedValue res(cx);
+    if (!xpc::CreateObjectIn(cx, rvobj, options, &res))
         return NS_ERROR_FAILURE;
 
-    *rval = ObjectValue(*obj);
+    *rval = res;
     return NS_OK;
 }
 

js/xpconnect/src/xpcprivate.h

@@ -3627,10 +3627,11 @@ public:
     virtual bool Parse() = 0;
 
 protected:
-    bool ParseValue(const char *name, JS::MutableHandleValue prop, bool *found);
+    bool ParseValue(const char *name, JS::MutableHandleValue prop, bool *found = nullptr);
     bool ParseBoolean(const char *name, bool *prop);
     bool ParseObject(const char *name, JS::MutableHandleObject prop);
     bool ParseString(const char *name, nsCString &prop);
+    bool ParseId(const char* name, JS::MutableHandleId id);
 
     JSContext *mCx;
     JS::RootedObject mObject;
@@ -3664,6 +3665,19 @@ protected:
     bool ParseGlobalProperties();
 };
 
+class MOZ_STACK_CLASS CreateObjectOptions : public OptionsBase {
+public:
+    CreateObjectOptions(JSContext *cx = xpc_GetSafeJSContext(),
+                        JS::HandleObject options = JS::NullPtr())
+        : OptionsBase(cx, options)
+        , defineAs(cx, JSID_VOID)
+    { }
+
+    virtual bool Parse() { return ParseId("defineAs", &defineAs); };
+
+    JS::RootedId defineAs;
+};
+
 JSObject *
 CreateGlobalObject(JSContext *cx, const JSClass *clasp, nsIPrincipal *principal,
                    JS::CompartmentOptions& aOptions);
@@ -3706,6 +3720,10 @@ nsresult
 SetSandboxMetadata(JSContext *cx, JS::HandleObject sandboxArg,
                    JS::HandleValue metadata);
 
+bool
+CreateObjectIn(JSContext *cx, JS::HandleValue vobj, CreateObjectOptions &options,
+               JS::MutableHandleValue rval);
+
 } /* namespace xpc */