os::net: expanding TcpStreamExt for Linux with `tcp_deferaccept`.

allows for socket to process only when there is data to process,
the option sets a number of seconds until the data is ready.

1 files changed, 26 insertions, 0 deletions

diff --git a/library/std/src/os/net/linux_ext/tests.rs b/library/std/src/os/net/linux_ext/tests.rs
index 2db4deed036..f8dbbfc18e2 100644
--- a/library/std/src/os/net/linux_ext/tests.rs
+++ b/library/std/src/os/net/linux_ext/tests.rs
@@ -26,3 +26,29 @@ fn quickack() {
     t!(stream.set_quickack(false));
     assert_eq!(false, t!(stream.quickack()));
 }
+
+#[test]
+#[cfg(target_os = "linux")]
+fn deferaccept() {
+    use crate::{
+        net::{test::next_test_ip4, TcpListener, TcpStream},
+        os::net::linux_ext::tcp::TcpStreamExt,
+    };
+
+    macro_rules! t {
+        ($e:expr) => {
+            match $e {
+                Ok(t) => t,
+                Err(e) => panic!("received error for `{}`: {}", stringify!($e), e),
+            }
+        };
+    }
+
+    let addr = next_test_ip4();
+    let _listener = t!(TcpListener::bind(&addr));
+    let stream = t!(TcpStream::connect(&("localhost", addr.port())));
+    stream.set_deferaccept(1).expect("set_deferaccept failed");
+    assert_eq!(stream.deferaccept().unwrap(), 1);
+    stream.set_deferaccept(0).expect("set_deferaccept failed");
+    assert_eq!(stream.deferaccept().unwrap(), 0);
+}