Add local_addr and ttl functions to TcpAcceptor (#640)

* Add local_addr and ttl functions to `TcpAcceptor`

* Format Rust code using rustfmt

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

crates/core/src/conn/tcp.rs

@@ -1,5 +1,6 @@
 //! TcpListener and it's implements.
 use std::io::{Error as IoError, ErrorKind, Result as IoResult};
+use std::net::SocketAddr;
 use std::sync::Arc;
 use std::time::Duration;
 use std::vec;
@@ -112,6 +113,29 @@ pub struct TcpAcceptor {
     holdings: Vec<Holding>,
 }
 
+impl TcpAcceptor {
+    /// Returns the local address that this listener is bound to.
+    ///
+    /// This can be useful, for example, when binding to port 0 to figure out
+    /// which port was actually bound.
+    pub fn local_addr(&self) -> IoResult<SocketAddr> {
+        self.inner.local_addr()
+    }
+
+    /// Gets the value of the `IP_TTL` option for this socket.
+    pub fn ttl(&self) -> IoResult<u32> {
+        self.inner.ttl()
+    }
+
+    /// Sets the value for the `IP_TTL` option on this socket.
+    ///
+    /// This value sets the time-to-live field that is used in every packet sent
+    /// from this socket.
+    pub fn set_ttl(&self, ttl: u32) -> IoResult<()> {
+        self.inner.set_ttl(ttl)
+    }
+}
+
 impl TryFrom<TokioTcpListener> for TcpAcceptor {
     type Error = IoError;
     fn try_from(inner: TokioTcpListener) -> Result<Self, Self::Error> {