Closes#766
- changes the on-disk representation from % to a multiplier,
eg 250 -> 2.5, as this is consistent with the other options
- resets deck configs at or below 1.3 to 2.5
- for any cards that were using a reset deck config, reset their
current factor if it's at or below 2.0x. The cutoff is arbitrary,
and just intended to make sure we catch cards the user has rated
Easy on multiple times. The existing due dates are left alone.
The previous implementation had some slightly questionable memory safety
properties (older versions of PyO3 didn't uphold the Rust aliasing rules
and would thus create multiple &mut references to #[pyclass] objects).
This explains why Backend has internal Mutex<T>s even though all of its
methods took &mut self.
The solution is to simply make all methods take &self, which luckily
doesn't pose too make issues -- most of the code inside Backend already
has sufficient locking. The only two things which needed to be
explicitly handled where:
1. "self.runtime" which was fairly easy to handle. All usages of
the Runtime only require an immutable reference to create a new
Handle, so we could switch to OnceCell which provides
lazy-initialisation semantics without needing a more heavy-handed
Mutex<tokio::runtime::Handle>.
2. "self.sync_abort" was simply wrapped in a Mutex<>, though some of the
odd semantics of sync_abort (not being able to handle multiple
processes synchronising at the same time) become pretty obvious with
this change (for now we just log a warning in that case). In
addition, switch to an RAII-style guard to make sure we don't forget
to clear the abort_handle.
As a result, we now no longer break Rust's aliasing rules and we can
build with newer versions of PyO3 which have runtime checks for these
things (and build on stable Rust).
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Previously, it was not possible to add a substring of an existing tag.
For example, with the tag "foobar", you could not add the tag "foo",
"bar" or "oob".
Because the match was unanchored, the regex checking whether the tag
already existed determined that the tag was present when it was not.
We need to be a bit conservative here due to buffer bloat - in the
upload case on a slow link, it can appear that no I/O is happening
when a buffer is draining.
