rich_nlas feature is non-additive (and makes nla docs confusing)

[eric-seppanen]

I tried writing some code using the netlink-packet-sock-diag crate, using docs.rs to understand the Nla enum. According to those docs, the TcpInfo variant contains a Vec<u8>, which I took to mean that decoding isn't available for this data structure.

I was surprised when I looked at the source code and discovered that decoding was present but required a feature flag. Perhaps the docs for this enum should contain a note that decoding requires a feature flag to be enabled?

I also notice that enabling the feature flag makes incompatible changes to the enum contents, making code no longer compile. This is a non-additive feature; it would be better to follow Cargo's guidance and ensure that enabling features doesn't break the existing public API.

[cathay4t]

Hi @eric-seppanen We are planning to remove this rich_nlas feature and stabilize our API slowly. Sorry for the mess up.

[kamyuentse]

I encountered the same issue today. And the TcpInfo length is variant with different kernel version.

@cathay4t As you say, the rich_nlas would be removed in the future release? And, for now, the only way to extract tcp info is writting a custom parser?