Downgrades a bunch of not-useful-at-info-level debug messages from info
-> debug. This makes `info` a more useful value for a client that wants
messages about startup/shutdown but not random non-serious connection
related messages.
We really don't *ever* want send to block, no matter how it is called,
since the send is always in the proxy thread. This makes the actual
send call always non-blocking, and adds callbacks that we can invoke on
send failures: either on queue full errors (which might be recoverable),
or both full queue and hard failures (which are generally not
recoverable). These callbacks are both optional: they have to be passed
in using `send_option::queue_full` (if you just want queue full
notifies) or `send_option::queue_failure` (if you want queue full
notifies *and* other send exceptions).
When we try to route an internal message ("BYE", "NOT_A_SERVICE_NODE",
etc.) back to the remote from the proxy thread we can end up trying to
send to a disconnected remote, which raises an exception, but this isn't
caught in proxy code: fix this by catching and ignoring it.
This also changes the code to send these messages in "dontwait" mode so
that if we can't queue the message we get (and ignore) an exception
rather than blocking.
When we fail to send to a SN but can retry (e.g. because we had an
incoming connection which no longer works, but can retry an outgoing
connection) we were recursing, but this was resulting in a double-free
of the request callback (since we'd try to take ownership of the
incoming serialized pointer twice).
Rewrite the code to use a loop with single ownership instead.
This also changes the request callback behaviour to fire a failure
callback immediately if we can't send a request; previously you'd have
to wait for a timeout, but that is pointless if we couldn't get the
request out.
For example:
lmq.request(conn, "some.method", callback, lokimq::request_timeout{5s});
will result in the callback being called with a failure if the response
doesn't arrive within 5s. (If it still arrives, but after the failure
callback, it gets dropped).
The previous 1s default seems on the long side; this reduces it to
250ms. It also makes it a public member so that it can be configured
(which is mainly needed for the test suite, but might be useful for
lokimq-calling code that needs faster or slower connection cleanups).
Having this as a vector seems to cause armhf/gcc-6 to segfault. On
closer inspection there's no good reason this should be a vector in the
first place: it only gets used during new connection handshaking and
isn't in any hot loop, plus the elements are fairly large tuples where
shifting elements is going to be relatively expensive. Thus switching
it to a list everywhere (rather than just on old gcc arm) seems fine.
- Don't try to use cppzmq, just find libzmq ourselves.
- Allow existing `libzmq` and `sodium` targets to be used to control how
we link to libzmq and/or sodium.
- Use PkgConfig:: targets instead of the older bunch-of-variables
approach (requires cmake >= 3.6).
lokimq.cpp and lokimq.h were getting monolithic; this splits lokimq.cpp
into multiple smaller cpp files by logical purpose for better parallel
compilation ability. It also splits up the lokimq.h header slightly by
moving the ConnectionID and Message types into their own headers.
Depend on cppzmq-static when doing a static build.
cppzmq-static itself has a dependency problem with libsodium, so
explicitly set the missing but required libsodium dependency on it.
This removes two superfluous erases that occur during connection closing
(the proxy_close_connection just above them already removes the element
from `peers`), and also short-circuits the incoming message loop if our
pollitems becomes stale so that we don't try to use a closed connection.
It also fixes a bug in the outgoing connection index that was
decrementing the wrong connection indices, leading to failures when
trying to send on an existing connection after a disconnect.
Also adds a test case (which fails before the changes in this commit) to
test this.
Jason Rhinelander