This involves making a temporary ErrorKind::TODO. That will continue
to exist until all errors (at least, the ones that make it out to
here) can be properly categorised.
Introducing this will let us work from the top and bottom towards the
middle.
Provide an enum variant to contain the SpawnError and a From impl.
We use `#[from]` here because it doesn't really make sense to attach
any context, as it's not likely to be very relevant.
This needs two kinds. We have decided to treat a non-shutdown
SpawnError as "unexplained" rather than as an InternalError.
There are many crates whose
From<futures::task::SpawnError> for Error
erroneously treat it as an internal error. We will fix them in a moment.
Serialisation errors ought not to occur, since they would represent an
attempt to store malformed data, or something. (We always convert to
a string, so the JSON error never contains IO errors or the like.)
Deserialisation errors mean the persistent state is corrupt.
The type annotation may not be necessary for inference, but as a
comment it risks becoming false. So it should be uncommented, or
deleted.
Error types round here are not entirely trivial so uncomment it.
(More specifically, `notify` behaves differently on different
platforms. On some, it can watch specific directory objects on the
filesystem, and so it only notices when _those_ directories change.
If you change a symlink so that the canonical configuration file
location is now in some other directory, `notify` won't notice. But
on other platforms, notify just does "stat()" in a loop. On those,
it _will_ notice if the configuration file changes.)
A number of severe problems with the circuit reactor were fixed which
could cause reordering of cells (which causes relays to terminate the
circuit with a protocol violation, as they become unable to decrypt
them). These mostly revolve around improper usage of queues:
- The code assumed that a failure to place cells onto the channel would
persist for the duration of a reactor cycle run. However, under high
contention, this wouldn't always be the case.
- This leads to some cells getting enqueued while others go straight
through, before the enqueued cells.
- To fix this, we block sending cells out of the channel while there
are still some enqueued.
- The hop-specific queues queued after encryption, not before. This was
very brittle, and led to frequent mis-ordering.
- This was fixed by making them not do that.
This is arti!264 / 5bce9db562 without the
refactor part.
Since the user can put their logfiles and configuration files in the
same directory, writing to the log can trigger an event from
`notify`. If we log every non-interesting event from `notify`, then
we'll trigger the logs every time we log, and fill up the disk.
This commit removes the offending log and adds a comment about why.
If we someday decide we do need to log here, maybe we can rate-limit
the messages or something.
Due to limitations in notify and the OS APIs it uses, it isn't
actually so useful to watch a single file. Instead, we have to
watch the directories that contain the files, and filter out any
events that aren't about the specific files we care about.
I've put the logic here into a new type, but I've left the type
un-exported: its API is pretty ugly, inasmuch as the caller needs to
jump through hoops to only get the events that they want. That's
not too bad so long as the API is private, but we'd want better if
we were exposing this.
Prompted by clippy::needless_question_mark. Sometimes Ok(r?) is
needed to do automatic error conversion. I assume the lint checks for
that. Anyway, in these cases it's not needed.
clippy::needless_borrow quibbles here, IMO correctly. Its suggestion
didn't go far enough: output is a String and a &String can be passed
to write as-is for identical effect.
Ian Jackson
eta
Ian Jackson
Daniel Schischkin
Nick Mathewson
Dimitris Apostolou