[PATCH 3/3 optional] kernel32/tests: Add GetQueuedCompletionPort race condition test

[Andrew Eikum]

Signed-off-by: Andrew Eikum 
---

This patch is optional. It demonstrates the race condition described
in the first patch. Without the fixes applied, Wine always fails in
fewer than 50 runs on my machine. Windows never fails. Since it's a
race condition, it's always going to be flaky, so I'm not sure whether
it's useful to add these tests (and the added test runtime).

dlls/kernel32/tests/process.c | 80 ++++++++++++++++++++++++++++++++++-
 1 file changed, 78 insertions(+), 2 deletions(-)

diff --git a/dlls/kernel32/tests/process.c b/dlls/kernel32/tests/process.c
index 0d1a2f1a31d..cdcc564d006 100644
--- a/dlls/kernel32/tests/process.c
+++ b/dlls/kernel32/tests/process.c
@@ -2776,12 +2776,43 @@ static void test_QueryInformationJobObject(void)
     CloseHandle(job);
 }

+static struct completion_port_test_data {
+    HANDLE port;
+    HANDLE wait_evt;
+    BOOL quit;
+} completion_port_test_data;
+
+static DWORD WINAPI completion_port_test_threadproc(void *user)
+{
+    while (!completion_port_test_data.quit)
+    {
+        WaitForSingleObject(completion_port_test_data.wait_evt, INFINITE);
+        if (completion_port_test_data.quit)
+        {
+            CloseHandle(completion_port_test_data.port);
+            break;
+        }
+
+        Sleep(10); /* allow main thread to settle into GetQueued() */
+
+        PostQueuedCompletionStatus(completion_port_test_data.port, 1, 0, (OVERLAPPED*)&completion_port_test_data);
+        CloseHandle(completion_port_test_data.port);
+
+        SetEvent(completion_port_test_data.wait_evt);
+    }
+    return 0;
+}
+
 static void test_CompletionPort(void)
 {
     JOBOBJECT_ASSOCIATE_COMPLETION_PORT port_info;
     PROCESS_INFORMATION pi, pi2;
-    HANDLE job, port;
-    BOOL ret;
+    HANDLE job, port, thread;
+    BOOL ret, failed;
+    int tries;
+    DWORD bytes_transferred;
+    ULONG_PTR key;
+    OVERLAPPED *overlapped;

job = pCreateJobObjectW(NULL, NULL);
     ok(job != NULL, "CreateJobObject error %u\n", GetLastError());
@@ -2822,6 +2853,50 @@ static void test_CompletionPort(void)
     CloseHandle(pi.hThread);
     CloseHandle(job);
     CloseHandle(port);
+
+    /* no race condition between blocked GetQueuedCompletionStatus and CloseHandle(port) */
+    completion_port_test_data.quit = FALSE;
+    completion_port_test_data.wait_evt = CreateEventW(NULL, FALSE, FALSE, NULL);
+    thread = CreateThread(NULL, 0, &completion_port_test_threadproc, NULL, 0, NULL);
+
+    failed = FALSE;
+    tries = 0;
+    while (tries < 100 && !failed)
+    {
+        completion_port_test_data.port = pCreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 1);
+        ok(completion_port_test_data.port != NULL, "%u: CreateIoCompletionPort error %u\n", tries, GetLastError());
+
+        SetEvent(completion_port_test_data.wait_evt);
+
+        bytes_transferred = 0xdeadbeef;
+        key = 0xdeadbeee;
+        overlapped = (OVERLAPPED*)0xdeadbeed;
+
+        ret = GetQueuedCompletionStatus(completion_port_test_data.port, &bytes_transferred, &key,
+                &overlapped, INFINITE);
+        ok(ret == TRUE, "%u: GetQueuedCompletionStatus failed: %u\n", tries, GetLastError());
+        if (ret == TRUE)
+        {
+            ok(bytes_transferred == 1, "%u: got bt: 0x%x\n", tries, bytes_transferred);
+            ok(key == 0, "%u: got key: 0x%x\n", tries, key);
+            ok(overlapped == (OVERLAPPED*)&completion_port_test_data, "%u: got overlapped: %p\n", tries, overlapped);
+        }
+        else
+            failed = TRUE;
+
+        ++tries;
+
+        /* wait for other thread to be ready for next test */
+        WaitForSingleObject(completion_port_test_data.wait_evt, INFINITE);
+    }
+
+    completion_port_test_data.quit = TRUE;
+    SetEvent(completion_port_test_data.wait_evt);
+
+    WaitForSingleObject(thread, INFINITE);
+
+    CloseHandle(thread);
+    CloseHandle(completion_port_test_data.wait_evt);
 }

static void test_KillOnJobClose(void)
@@ -5055,6 +5130,7 @@ START_TEST(process)
     }
     else
         win_skip("PROCESS_QUERY_LIMITED_INFORMATION is not supported on this platform\n");
+
     test_process_info(GetCurrentProcess());
     test_TerminateProcess();
     test_Startup();