implement TryFrom<std::net::UdpSocket/TcpListener> for UdpSocket/TcpListener

[vavrusa]

This allows setting various socket options (e.g. SO_REUSEPORT) before
binding to the socket, and also socket passing from the service supervisor (e.g. systemd).

[yoshuawuyts]

Hey thanks so much for this patch!

For work we encountered a similar situation recently (around mio also), and something that came out of it is that if a std component can't be changed to a mio variant, something terrible has gone wrong, and it's probably safe to abort the process.

Which is to say: I think it'd be entirely reasonable to use From rather than TryFrom for these conversions.

[kpp]

Which is to say: I think it'd be entirely reasonable to use From rather than TryFrom for these conversions.

Let the user fail as they want =)

[vavrusa]

It will probably be okay, but I didn't feel confident burying .unwrap() in a fundamental library for just a slightly easier use (this is also not something that will be used that often I guess). That being said, I'm happy to change it if your consensus is to go with From trait instead.

[vavrusa]

Just to clarify - the "👍" means "it's ok to keep it as it is", "please change it to From", or "undecided" ?

[kpp]

I am against .unwrap() in a library code

[yoshuawuyts]

@vavrusa yeah, I'd prefer if it was From rather than TryFrom. If this fails then something terrible has gone wrong on the mio side, and it's probably best to abort.

@kpp Sorry, but that feels like an arbitrary restriction. If we were to follow that then romio in its current form wouldn't even be able to exist.

[kpp]

Sorry, but that feels like an arbitrary restriction.

It's not. You can add both TryFrom and From, but implement From as try_from().unwrap(). Having only From implemented with .unwrap() is a restriction.