Fix Harmony-707 test for CTS

Change the way Harmony-707 test works.
We cannot check timeouts equality, as timeout is approximated
by the Linux Kernel (see set_sock_timeout() in net/core/sock.c).

Previously, testing with the value provided to setSoTimout()
could fail, depending on the Kernel configuration:
- On a device running a kernel compiled with CONFIG_HZ=100,
  it would work
- On a device running a kernel compiled with CONFIG_HZ=250,
  it would not:
  * Kernel stored a timeout of 3 (3.49975 cast to long)
   *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ)
   with tv.tv_sec=0, tv.tv_usec=10000 (10ms), and HZ=250
  * Kernel returned a timeout of 12ms
   v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ
   with sk->sk_rcvtimeo=3 and HZ=250

Instead, we have to ensure that the timeout is not reset to the
internal default timeout after calling accept():
 - set a timeout
 - immediately retrieve it and store it (this value may differ
   from the previously set value)
 - call accept()
 - retrieve and check the timeout with the previously stored
   timeout

Change-Id: I7f05c6843d9e48e6d696dca17173fce028a45a68
Signed-off-by: Samuel Rats <samuel.rats@gmail.com>

1 files changed, 21 insertions, 6 deletions

diff --git a/harmony-tests/src/test/java/org/apache/harmony/tests/java/nio/channels/ServerSocketChannelTest.java b/harmony-tests/src/test/java/org/apache/harmony/tests/java/nio/channels/ServerSocketChannelTest.java
index c1d592a..be40d0b 100644
--- a/harmony-tests/src/test/java/org/apache/harmony/tests/java/nio/channels/ServerSocketChannelTest.java
+++ b/harmony-tests/src/test/java/org/apache/harmony/tests/java/nio/channels/ServerSocketChannelTest.java
@@ -657,20 +657,35 @@ public class ServerSocketChannelTest extends TestCase {
      * @tests ServerSocketChannel#socket().getSoTimeout()
      */
     public void test_accept_SOTIMEOUT() throws IOException {
-        // regression test for Harmony-707
-        final int SO_TIMEOUT = 10;
+        // Regression test for Harmony-707
+        // The timeout actually used may be different from the one set due to
+        // rounding by the Linux Kernel (see sock_set_timeout() in net/core/sock.c).
+        // getSoTimeout() can return a different value from the one set with
+        // setSoTimeout(). Consequently we do not check for equality with what was
+        // set.
+
         ServerSocketChannel sc = ServerSocketChannel.open();
         try {
             sc.socket().bind(null);
+
+            // Non blocking mode, accept() will return NULL since there are no pending connections.
             sc.configureBlocking(false);
+
             ServerSocket ss = sc.socket();
+
+            int defaultTimeout = ss.getSoTimeout();
+            assertEquals(0, defaultTimeout);
+            // The timeout value is unimportant, providing it is large enough to be accepted
+            // by the Kernel as distinct from the default.
+            final int SO_TIMEOUT = 200;
             ss.setSoTimeout(SO_TIMEOUT);
+            int nonDefaultTimeout = ss.getSoTimeout();
+            assertTrue(nonDefaultTimeout != defaultTimeout);
+
             SocketChannel client = sc.accept();
-            // non blocking mode, returns null since there are no pending connections.
             assertNull(client);
-            int soTimeout = ss.getSoTimeout();
-            // Harmony fails here.
-            assertEquals(SO_TIMEOUT, soTimeout);
+            // Confirm the timeout was unchanged.
+            assertEquals(nonDefaultTimeout, ss.getSoTimeout());
         } finally {
             sc.close();
         }