C / C ++ or Bash script to sign jar files

Is there any C / C ++ code or Bash script that can sign Java.jar files without using the JVM? Such code can be useful for embedded applications that serve the jar file using a small HTTP server, or in other situations where the jar file might need to be edited and rewritten programmatically, but there is not enough storage space for the JVM.

Anyone need this type of Javaless jarsigner?