go-multiaddr feature: provide InterfaceMultiaddrsFor

net.InterfaceAddrs calls fail on android. This function allows specifying your own set of addresses, so another api can be used to avoid the issue.

See: https://github.com/multiformats/go-multiaddr/pull/255#issuecomment-2406974680

Closes #255

Mar 15 '25 12:03 tobil4sk

Is the idea that you'll override these functions with go:linkname?

Mar 17 '25 17:03 MarcoPolo

The way I'm using it is to always use InterfaceMultiaddrsFor instead of InterfaceMultiaddrs, which allows any api to be used to get the addresses.

I'm quite new to go so I'm not familiar with go:linkname. This is how I've patch a library that relies on go-multiaddr in line with this change: https://github.com/libp2p/go-libp2p/pull/3236

Mar 17 '25 21:03 tobil4sk

Can you show me how you'll use this change? I'm having a hard time understanding how exposing InterfaceMultiaddrsFor helps here. Thanks

Mar 20 '25 04:03 MarcoPolo

Can you show me how you'll use this change? I'm having a hard time understanding how exposing InterfaceMultiaddrsFor helps here. Thanks

Instead of relying on InterfaceMultiaddrs, a slice of net.Addr can be passed into InterfaceMultiaddrsFor which allows the caller to decide how to determine the addresses. See the line: https://github.com/libp2p/go-libp2p/pull/3236/files#diff-46c1cc328c2b33cbdce1bc123a2d6e06f5afc4758186638f9320673f8595ab0bR523

Additionally, when using manet.ResolveUnspecifiedAddresses, you have to avoid passing nil as the second argument to prevent it from calling InterfaceMultiaddrs internally. E.g.: https://github.com/libp2p/go-libp2p/pull/3236/files#diff-e544d19687434c7b654de15689302596c5159444ad1db181f7096473eb42e8f3R56-R68

Mar 20 '25 15:03 tobil4sk