### Purpose
Resend our indexes since we fixed that index-sending issue.
I made a new thing to only drop the non-local-device index IDs, i.e.,
those for other devices. This means we will see a mismatch and resend
all indexes, but they will not. This is somewhat cleaner as it avoids
resending everything twice when two devices are upgraded, and in any
case, we have no reason to force a resend of incoming indexes here.
### Testing
It happens on my computer...
This makes a couple of small improvements to the folder summary
mechanism:
- The folder summary includes the local and remote sequence numbers in
clear text, rather than some odd sum that I'm not sure what it was
intended to represent.
- The folder summary event is generated when appropriate, regardless of
whether there is an event listener. We did this before because
generating it was expensive, and we wanted to avoid doing it
unnecessarily. Nowadays, however, it's mostly just reading out
pre-calculated metadata, and anyway, it's nice if it shows up reliably
when running with -verbose.
The point of all this is to make it easier to use these events to judge
when devices are, in fact, in sync. As-is, if I'm looking at two
devices, it's very difficult to reliably determine if they are in sync
or not. The reason is that while we can ask device A if it thinks it's
in sync, we can't see if the answer is "yes" because it has processed
all changes from B, or if it just doesn't know about the changes from B
yet. With proper sequence numbers in the event we can compare the two
and determine the truth. This makes testing a lot easier.
This adds the BlocksHash field from the FileInfo to our API output. It
can be useful for debugging, or for external tools. I'm intentionally
leaving it as an opaque base64 string because no meaning should be
derived from it: it's just a string.
This adds support for syncing extended attributes on supported
filesystem on Linux, macOS, FreeBSD and NetBSD. Windows is currently
excluded because the APIs seem onerous and annoying and frankly the uses
cases seem few and far between. On Unixes this also covers ACLs as those
are stored as extended attributes.
Similar to ownership syncing this will optional & opt-in, which two
settings controlling the main behavior: one to "sync" xattrs (read &
write) and another one to "scan" xattrs (only read them so other devices
can "sync" them, but not apply any locally).
Co-authored-by: Tomasz Wilczyński <twilczynski@naver.com>
Also adds idle time and keepalive parameters because how this is
configured has changed in the new package version. The values are those
that seems like might already be default, if keep-alives were enabled,
which is not obvious from the doc comments.
Also, Go 1.19 gofmt reformatting of comments.
This adds support for syncing ownership on Unixes and on Windows. The
scanner always picks up ownership information, but it is not applied
unless the new folder option "Sync Ownership" is set.
Ownership data is stored in a new FileInfo field called "platform data". This
is intended to hold further platform-specific data in the future
(specifically, extended attributes), which is why the whole design is a
bit overkill for just ownership.
This changes the GC mechanism so that the first pass (which reads all
FileInfos to populate bloom filters with block & version hashes) can
happen concurrently with normal database operations.
The big gcMut still exists, and we grab it temporarily to block all
other modifications while we set up the bloom filters. We then release
the lock and let other things happen, with those other things also
updating the bloom filters as required. Once the first phase is done we
again grab the gcMut, knowing that we are the sole modifier of the
database, and do the cleanup.
I also removed the final compaction step.
This makes us use TLS 1.3+ on sync connections by default. A new option
`insecureAllowOldTLSVersions` exists to allow communication with TLS
1.2-only clients (roughly Syncthing 1.2.2 and older). Even with that
option set you get a slightly simplified setup, with the cipher suite
order fixed instead of auto detected.
