format: should we specify anything about signal-safety of the Cancel methods?

[lidavidm]

We added methods to request cancellation of the currently active operation, but should we require them to be signal-safe?

[lidavidm]

IMO I don't think we can require AdbcConnectionCancel etc. to be signal-safe, practically, just looking at implementations (e.g. FlightSQL, not to mention, is making a Go FFI call signal-safe in the first place since Go swaps out the stack?). (Postgres's is apparently safe, though!)

CC @zeroshade @pitrou

[zeroshade]

IMO I don't think we can require AdbcConnectionCancel etc. to be signal-safe, practically...

I know that with Go you can set signal handlers, but I've never tested it across cgo before so I don't know how well that would work.

[lidavidm]

Note that I'm talking about other code/user code making a call to AdbcConnectionCancel from a signal handler, not us setting a signal handler

[pitrou]

I don't think we should require that. Signal-safety is hard to achieve in practice. I'd rather transfer that responsability to the client, if they need to cancel something from a signal handler.