RFC: reducing wasted disk space from addon files

[Hans Leidekker]

On Wed, 2019-03-27 at 17:18 +0100, Alexandre Julliard wrote:
> Hans Leidekker <hans at codeweavers.com> writes:
> > Here's what a reference counted shared directory would look like.
> > The first patch implements the needed custom actions in a Wine dll,
> > which can be cross compiled with MinGW. 
> 
> It doesn't seem right to add a dll that doesn't exist on Windows. Also I
> don't think you can do such reference counting reliably. File locking is
> not supported on all filesystems, and you won't be able to cleanup if
> the app dies in the middle of an update.

I wasn't planning to submit that dll. If you can't do the locking you'd
fall back to a regular install. So yes, that limits shared directory
support to filesystems that support locking.

MSI should be able to handle interrupted installs. We may not support
all of that yet, but we make use of file hashes for example.