+impl List {
+ fn diff_from(&self, prev: &List) -> UpdateDiff {
+ let prev_index_set: HashSet<IfIndex> = prev.0.keys().cloned().collect();
+ let curr_index_set: HashSet<IfIndex> = self.0.keys().cloned().collect();
+ let added = curr_index_set.sub(&prev_index_set).into_iter().collect();
+ let removed = prev_index_set.sub(&curr_index_set).into_iter().collect();
+ let mut modified = HashMap::new();
+ for index in curr_index_set.intersection(&prev_index_set) {
+ if prev.0[index] == self.0[index] {
+ continue;
+ }
+ let prev_addr_set: HashSet<&IpAddr> = prev.0[index].ips.iter().collect();
+ let curr_addr_set: HashSet<&IpAddr> = self.0[index].ips.iter().collect();
+ let addrs_added: Vec<IpAddr> = curr_addr_set
+ .sub(&prev_addr_set)
+ .iter()
+ .cloned()
+ .cloned()
+ .collect();
+ let addrs_removed: Vec<IpAddr> = prev_addr_set
+ .sub(&curr_addr_set)
+ .iter()
+ .cloned()
+ .cloned()
+ .collect();
+ let hw_addr_changed = prev.0[index].hw_addr != self.0[index].hw_addr;
+ modified.insert(
+ *index,
+ InterfaceDiff {
+ hw_addr_changed,
+ addrs_added,
+ addrs_removed,
+ },
+ );
+ }
+ UpdateDiff {
+ added,
+ removed,
+ modified,
+ }
+ }
+}
+
+/// A handle to keep alive as long as you wish to receive callbacks.
+///
+/// If the callback is executing at the time the handle is dropped, drop will block until
+/// the callback is finished and it's guaranteed that it will not be called again.
+///
+/// Do not drop the handle from within the callback itself. It will probably deadlock.
+pub struct WatchHandle {
+ _inner: watch::WatchHandle,
+}
+
+/// Retrieve information about all enabled network interfaces and their IP addresses.
+///
+/// This is a once-off operation. If you want to detect changes over time, see `watch_interfaces`.
+pub fn list_interfaces() -> Result<HashMap<IfIndex, Interface>, Error> {
+ list::list_interfaces().map(|list| list.0)
+}
+
+/// Retrieve interface information and watch for changes, which will be delivered via callback.
+///
+/// If setting up the watch is successful, this returns a `WatchHandle` which must be kept for
+/// as long as the provided callback should operate.
+///
+/// The callback will fire once immediately with an initial interface list, and a diff as if
+/// there were originally no interfaces present.
+///
+/// This function will return an error if there is a problem configuring the watcher, or if there
+/// is an error retrieving the initial interface list.
+///
+/// We assume that if listing the interfaces worked the first time, then it will continue to work
+/// for as long as the watcher is running. If listing interfaces begins to fail later, those
+/// failures will be swallowed and the callback will not be called for that change event.
+pub fn watch_interfaces<F: FnMut(Update) + Send + 'static>(
+ callback: F,
+) -> Result<WatchHandle, Error> {
+ watch::watch_interfaces(callback).map(|handle| WatchHandle { _inner: handle })
+}