cred: isolate scripts in WASI and move RSA signing to AWS-LC

host/cred-script/vendor/llrt_utils_watts/src/module.rs

@@ -0,0 +1,29 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+use rquickjs::{
+    module::{Exports, ModuleDef},
+    Ctx, Object, Result, Value,
+};
+
+pub struct ModuleInfo<T: ModuleDef> {
+    pub name: &'static str,
+    pub module: T,
+}
+
+pub fn export_default<'js, F>(ctx: &Ctx<'js>, exports: &Exports<'js>, f: F) -> Result<()>
+where
+    F: FnOnce(&Object<'js>) -> Result<()>,
+{
+    let default = Object::new(ctx.clone())?;
+    f(&default)?;
+
+    for name in default.keys::<String>() {
+        let name = name?;
+        let value: Value = default.get(&name)?;
+        exports.export(name, value)?;
+    }
+
+    exports.export("default", default)?;
+
+    Ok(())
+}