Usually, EOFs are represented by returning 0 in the `read` APIs, at
least, this is what read(2) dictate.
As clever creature, we may sum zeroes sometimes (advanced form:
`buf->added(got)`) and forego handling the EOF condition.
To avoid the bug that lurked in remote-store.cc and caused busy looping
if the remote end disconnects suddenly, we return
`Result<Option<size_t>>` forcing the caller to perform a specific
processing for the EOF situation.
The conversion did not raise any other offending code path.
Change-Id: I185fdcb77aa82d87ab0802d66ac37c1363657a73
Signed-off-by: Raito Bezarius <raito@lix.systems>
Raito Bezarius
f8ccd9d572