net: fix OwnedWriteHalf behavior on drop (#2597)

Previously, dropping the Write handle would issue a `shutdown(Both)`. However,
shutting down the read half is not portable and not the correct action to take.

This changes the behavior of OwnedWriteHalf to only perform a `shutdown(Write)`
on drop.

2 files changed, 6 insertions, 6 deletions

diff --git a/tokio/src/net/tcp/split_owned.rs b/tokio/src/net/tcp/split_owned.rs
index ff82f6ed..3f6ee33f 100644
--- a/tokio/src/net/tcp/split_owned.rs
+++ b/tokio/src/net/tcp/split_owned.rs
@@ -40,7 +40,7 @@ pub struct OwnedReadHalf {
 /// Note that in the [`AsyncWrite`] implemenation of this type, [`poll_shutdown`] will
 /// shut down the TCP stream in the write direction.
 ///
-/// Dropping the write half will close the TCP stream in both directions.
+/// Dropping the write half will shutdown the write half of the TCP stream.
 ///
 /// Writing to an `OwnedWriteHalf` is usually done using the convenience methods found
 /// on the [`AsyncWriteExt`] trait. Examples import this trait through [the prelude].
@@ -209,9 +209,8 @@ impl OwnedWriteHalf {
     pub fn reunite(self, other: OwnedReadHalf) -> Result<TcpStream, ReuniteError> {
         reunite(other, self)
     }
-    /// Destroy the write half, but don't close the stream until the read half
-    /// is dropped. If the read half has already been dropped, this closes the
-    /// stream.
+
+    /// Drop the write half, but don't issue a TCP shutdown.
     pub fn forget(mut self) {
         self.shutdown_on_drop = false;
         drop(self);
@@ -221,7 +220,7 @@ impl OwnedWriteHalf {
 impl Drop for OwnedWriteHalf {
     fn drop(&mut self) {
         if self.shutdown_on_drop {
-            let _ = self.inner.shutdown(Shutdown::Both);
+            let _ = self.inner.shutdown(Shutdown::Write);
         }
     }
 }
diff --git a/tokio/src/net/tcp/stream.rs b/tokio/src/net/tcp/stream.rs
index 92c7c84e..319ef72e 100644
--- a/tokio/src/net/tcp/stream.rs
+++ b/tokio/src/net/tcp/stream.rs
@@ -652,7 +652,8 @@ impl TcpStream {
     /// Unlike [`split`], the owned halves can be moved to separate tasks, however
     /// this comes at the cost of a heap allocation.
     ///
-    /// **Note:** Dropping the write half will close the TCP stream in both directions.
+    /// **Note::** Dropping the write half will shutdown the write half of the TCP
+    /// stream. This is equivalent to calling `shutdown(Write)` on the `TcpStream`.
     ///
     /// [`split`]: TcpStream::split()
     pub fn into_split(self) -> (OwnedReadHalf, OwnedWriteHalf) {