I am looking for a system, preferably open source, that will help us manage code that is GPL and code that isn't. We are designing a fairly exhaustive hardware product that will rely heavily on open source code, but will also contain proprietary non-open source code.
We want a system to help keep track of the two, preventing us, for example, from putting proprietary code in GPL files. We want to maintain a clear delineation between the two. This will also help so when we receive a GPL request, we can easily furnish everything that is needed in a timely fashion without pulling our our hair trying to navigate hundreds of thousands of files to determine what we should and shouldn't provide.
Is there any sort of a code versioning tool that can maintain a separation between GPL and non-GPL code?