Previously we'd segfault in PQisnonblocking() which, contrary to other
libpq calls, doesn't handle a NULL PQconn (because there'd be no
appropriate return value for that).
A small refactor which pulls some code out of `RecoverWorkerTransactions`
and into `remote_commands.c`. This code block currently only occurs in
`RecoverWorkerTransactions` but will be useful to other functions
shortly.
Unfortunately we couldn't call it `ExecuteRemoteCommand`, that name was
already taken.
This includes basic infrastructure for logging of commands sent to
remote/worker nodes. Note that this has no effect as of yet, since no
callers are converted to the new infrastructure.
Andres Freund
Brian Cloutier
Marco Slot