Test that server socket cannot reuse port

net/socket/tcp_server_socket_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/socket/tcp_server_socket.h"
 
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
@@ skipping 228 matching lines @@
     ASSERT_TRUE(read_result >= 0);
     ASSERT_TRUE(bytes_read + read_result <= message.size());
     memmove(&buffer[bytes_read], read_buffer->data(), read_result);
     bytes_read += read_result;
   }
 
   std::string received_message(buffer.begin(), buffer.end());
   ASSERT_EQ(message, received_message);
 }
 
+TEST_F(TCPServerSocketTest, Rebind) {
+  IPEndPoint address;
+  // Bind to a random, unused port.
+  ParseAddress("127.0.0.1", 0, &address);
+
+  scoped_ptr<TCPServerSocket> socket(
+      new TCPServerSocket(NULL, NetLog::Source()));
+  ASSERT_EQ(OK, socket->Listen(address, kListenBacklog));
+
+  // Retrieve the real endpoint bound.
+  ASSERT_EQ(OK, socket->GetLocalAddress(&address));
+
+  scoped_ptr<TCPServerSocket> conflict_socket(
+      new TCPServerSocket(NULL, NetLog::Source()));
+  ASSERT_NE(OK, conflict_socket->Listen(address, kListenBacklog));
+
+  // Unbind.
+  socket.reset(NULL);
+
+  ASSERT_EQ(OK, conflict_socket->Listen(address, kListenBacklog));
+}
+
 }  // namespace
 
 }  // namespace net