We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
`it.is_end()` could be updated to return false for a previously-invalid
iterator after we append a new socket, copy its value out to a local
variable to not hit this behaviour.
This commit converts TLS::TLSv12 to a Core::Stream object, and in the
process allows TLS to now wrap other Core::Stream::Socket objects.
As a large part of LibHTTP and LibGemini depend on LibTLS's interface,
this also converts those to support Core::Stream, which leads to a
simplification of LibHTTP (as there's no need to care about the
underlying socket type anymore).
Note that RequestServer now controls the TLS socket options, which is a
better place anyway, as RS is the first receiver of the user-requested
options (though this is currently not particularly useful).
We previously only replaced disconnected sockets on the queued-request
path, leading to attempts to send requests on a disconnected socket if
the disconnection happened in the deletion grace period.
vdbgln() was responsible for ~10% of samples on pv's flamegraph for
RequestServer (under request_did_finish) when loading github.com in
Browser and recording a whole-system profile. This makes that almost
completely disappear.
Until we're confident that RequestServer doesn't need this runtime debug
dump helper, it's much nicer if everyone has it built in, so they can
simply send a SIGINFO if they see it acting up.
Just as removing individual connections can cause the vector entries to
change positions, adding or removing connections to the cache can also
move the connections around, which would make it possible for a
connection to avoid being deleted (and make the RS spin on the Notifier
for that connection).
This commit makes it so that no connection cache is left when it's
supposed to be deleted.
Fixes a few more RS spins.
Otherwise we'd end up trying to delete the wrong connection if a
connection made before us is deleted.
Fixes _some_ RequestServer spins (though not all...).
This commit also adds a small debug mechanism to RequestServer (which
can be enabled by turning REQUEST_SERVER_DEBUG on), that can dump all
the current active connections in the cache, what they're doing, and how
long they've been doing that by sending it a SIGINFO.
This makes connections (particularly TLS-based ones) do the handshaking
stuff only once.
Currently the cache is configured to keep at most two connections evenly
balanced in queue size, and with a grace period of 10s after the last
queued job has finished (after which the connection will be dropped).
