Function JS_Ext_NewCFunctionMagic 

pub unsafe extern "C" fn JS_Ext_NewCFunctionMagic(
    ctx: *mut JSContext,
    func: JSCFunctionMagic,
    name: *const c_char,
    length: c_int,
    cproto: JSCFunctionEnum,
    magic: c_int,
) -> JSValue