From ca7fb82e0b9fb47e4addcee7b993993e7ce27fde Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Sun, 29 Jun 2014 09:38:07 -0700
Subject: rustuv: Don't zero-out data on clones

When cloning a stream, the data is already guaranteed to be in a consistent
state, so there's no need to perform a zeroing. This prevents segfaults as seen
in #15231

Closes #15231
---
 src/libstd/io/net/tcp.rs | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

(limited to 'src/libstd/io')

diff --git a/src/libstd/io/net/tcp.rs b/src/libstd/io/net/tcp.rs
index b79e831ff61..baf53251fbe 100644
--- a/src/libstd/io/net/tcp.rs
+++ b/src/libstd/io/net/tcp.rs
@@ -1360,4 +1360,44 @@ mod test {
 
         rx2.recv();
     })
+
+    iotest!(fn clone_while_reading() {
+        let addr = next_test_ip6();
+        let listen = TcpListener::bind(addr.ip.to_str().as_slice(), addr.port);
+        let mut accept = listen.listen().unwrap();
+
+        // Enqueue a task to write to a socket
+        let (tx, rx) = channel();
+        let (txdone, rxdone) = channel();
+        let txdone2 = txdone.clone();
+        spawn(proc() {
+            let mut tcp = TcpStream::connect(addr.ip.to_str().as_slice(),
+                                             addr.port).unwrap();
+            rx.recv();
+            tcp.write_u8(0).unwrap();
+            txdone2.send(());
+        });
+
+        // Spawn off a reading clone
+        let tcp = accept.accept().unwrap();
+        let tcp2 = tcp.clone();
+        let txdone3 = txdone.clone();
+        spawn(proc() {
+            let mut tcp2 = tcp2;
+            tcp2.read_u8().unwrap();
+            txdone3.send(());
+        });
+
+        // Try to ensure that the reading clone is indeed reading
+        for _ in range(0i, 50) {
+            ::task::deschedule();
+        }
+
+        // clone the handle again while it's reading, then let it finish the
+        // read.
+        let _ = tcp.clone();
+        tx.send(());
+        rxdone.recv();
+        rxdone.recv();
+    })
 }
-- 
cgit 1.4.1-3-g733a5