This changes `split_off`, which does one allocation and copies `n` items
in the best case, `2 * n` items in the worst case to `retain`, which does
zero allocations and copies zero items in the best case and `3 * (n - 1)`
items in worst case (because swap is 3 copies and `retain` has to swap
due to possibility of panic).
I believe this should be net-benefit due to usually small `n`.
This change implements non-blocking cleanup of threads. It achieves it
by cleaning up periodically based on thread ID, that gets sent from dead
thread over a channel. Aside from internal locks in the channel, there
are no other locks. The cleanup also happens only after a new connection
is accepted, but hopefully won't be an issue, unless there are many
connections that die and then nothing connects for a long time. A final
cleanup happens when the thread is finishing.
After a recent switch to configure_me in ec049b9a, the 'mainnet'
arg value became 'bitcoin'. 2c50791d then updated db dir location
but the doc for the --network arg remained stale.
An alternative is to accept both 'mainnet' and 'bitcoin' but
it would be confusing IMHO.
This change allows the user to specify a custom cookie file, which is then
used instead of `~/.bitcoin/.cookie`. This resolves situations when the
user wants to have the cookie file in non-standard path.
Aside from that, the code now pre-computes the default path, improving
the performance by avoiding allocation (and copying). Unfortunately, due
to limitations of Rust, the code doesn't print out cookie configuration
anymore. This however might be safer, since the cookie isn't printed,
and thus doesn't end up in some readable logs by accident.
Closes#176Closes#189
Also, move TransactionCache into `cache` module.
Following https://github.com/romanz/electrs/pull/161 by @dagurval.
Co-authored-by: Dagur Valberg Johannsson <dagurval@pvv.ntnu.no>
