diff -r 000000000000 -r 6474c204b198 ipc/ipdl/test/cxx/TestUrgency.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ipc/ipdl/test/cxx/TestUrgency.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,186 @@
+#include "TestUrgency.h"
+
+#include "IPDLUnitTests.h"      // fail etc.
+#if defined(OS_POSIX)
+#include <unistd.h>
+#else
+#include <windows.h>
+#endif
+
+template<>
+struct RunnableMethodTraits<mozilla::_ipdltest::TestUrgencyParent>
+{
+    static void RetainCallee(mozilla::_ipdltest::TestUrgencyParent* obj) { }
+    static void ReleaseCallee(mozilla::_ipdltest::TestUrgencyParent* obj) { }
+};
+
+namespace mozilla {
+namespace _ipdltest {
+
+#if defined(OS_POSIX)
+static void Sleep(int ms)
+{
+    sleep(ms / 1000);
+}
+#endif
+
+//-----------------------------------------------------------------------------
+// parent
+
+TestUrgencyParent::TestUrgencyParent()
+  : inreply_(false)
+{
+    MOZ_COUNT_CTOR(TestUrgencyParent);
+}
+
+TestUrgencyParent::~TestUrgencyParent()
+{
+    MOZ_COUNT_DTOR(TestUrgencyParent);
+}
+
+void
+TestUrgencyParent::Main()
+{
+  if (!SendStart())
+    fail("sending Start");
+}
+
+bool
+TestUrgencyParent::RecvTest1(uint32_t *value)
+{
+  if (!CallReply1(value))
+    fail("sending Reply1");
+  if (*value != 99)
+    fail("bad value");
+  return true;
+}
+
+bool
+TestUrgencyParent::RecvTest2()
+{
+  uint32_t value;
+  inreply_ = true;
+  if (!CallReply2(&value))
+    fail("sending Reply2");
+  inreply_ = false;
+  if (value != 500)
+    fail("bad value");
+  return true;
+}
+
+bool
+TestUrgencyParent::RecvTest3(uint32_t *value)
+{
+  if (inreply_)
+    fail("nested non-urgent on top of urgent rpc");
+  *value = 1000;
+  return true;
+}
+
+bool
+TestUrgencyParent::RecvFinalTest_Begin()
+{
+  SetReplyTimeoutMs(2000);
+  if (CallFinalTest_Hang())
+    fail("should have failed due to timeout");
+  if (!GetIPCChannel()->Unsound_IsClosed())
+    fail("channel should have closed");
+
+  MessageLoop::current()->PostTask(
+      FROM_HERE,
+      NewRunnableMethod(this, &TestUrgencyParent::Close));
+  return false;
+}
+
+//-----------------------------------------------------------------------------
+// child
+
+enum {
+  kFirstTestBegin = 1,
+  kFirstTestGotReply,
+  kSecondTestBegin,
+  kSecondTestGotReply,
+};
+
+bool
+TestUrgencyChild::RecvStart()
+{
+  uint32_t result;
+  
+  // Send a synchronous message, expect to get an urgent message while
+  // blocked.
+  test_ = kFirstTestBegin;
+  if (!SendTest1(&result))
+    fail("calling SendTest1");
+  if (result != 99)
+    fail("bad result in RecvStart");
+  if (test_ != kFirstTestGotReply)
+    fail("never received urgent message");
+
+  // Initiate the next test by sending an asynchronous message, then becoming
+  // blocked. This tests that the urgent message is still delivered properly,
+  // and that the parent does not try to service the sync 
+  test_ = kSecondTestBegin;
+  if (!SendTest2())
+    fail("calling SendTest2");
+  if (!SendTest3(&result))
+    fail("calling SendTest3");
+  if (test_ != kSecondTestGotReply)
+    fail("never received urgent message #2");
+  if (result != 1000)
+    fail("wrong value from test3");
+
+  // This must be the last test, since the child process may die.
+  if (SendFinalTest_Begin())
+    fail("Final test should not have succeeded");
+
+  Close();
+
+  return true;
+}
+
+bool
+TestUrgencyChild::AnswerReply1(uint32_t *reply)
+{
+  if (test_ != kFirstTestBegin)
+    fail("wrong test # in AnswerReply1");
+
+  *reply = 99;
+  test_ = kFirstTestGotReply;
+  return true;
+}
+
+bool
+TestUrgencyChild::AnswerReply2(uint32_t *reply)
+{
+  if (test_ != kSecondTestBegin)
+    fail("wrong test # in AnswerReply2");
+
+  // sleep for 5 seconds so the parent process tries to deliver more messages.
+  Sleep(5000);
+
+  *reply = 500;
+  test_ = kSecondTestGotReply;
+  return true;
+}
+
+bool
+TestUrgencyChild::AnswerFinalTest_Hang()
+{
+  Sleep(10);
+  return true;
+}
+
+TestUrgencyChild::TestUrgencyChild()
+  : test_(0)
+{
+    MOZ_COUNT_CTOR(TestUrgencyChild);
+}
+
+TestUrgencyChild::~TestUrgencyChild()
+{
+    MOZ_COUNT_DTOR(TestUrgencyChild);
+}
+
+} // namespace _ipdltest
+} // namespace mozilla