Changeset 64975 in vbox

Timestamp:

Dec 21, 2016 12:24:25 PM (8 years ago)

Author:

vboxsync

Message:

Main: fixed a race and removed the (now) superfluous ThreadTask::createThreadWithRaceCondition() method. Under no circumstances we must use the thread handle after the thread creation call succeeded -- because the thread could have terminated in the meantime.

Location:

trunk/src/VBox/Main

Files:

• include/ThreadTask.h (modified) (3 diffs)
• src-all/ThreadTask.cpp (modified) (4 diffs)

trunk/src/VBox/Main/include/ThreadTask.h

@@ -36 +36 @@
     ThreadTask(const Utf8Str &t)
         : m_strTaskName(t)
-        , mAsync(false)
+        , mAsync(true)
     { }
 
@@ -44 +44 @@
     HRESULT createThread(void);
     HRESULT createThreadWithType(RTTHREADTYPE enmType);
-    HRESULT createThreadWithRaceCondition(PRTTHREAD pThread);
 
     inline Utf8Str getTaskName() const { return m_strTaskName; }
@@ -50 +49 @@
 
 protected:
-    HRESULT createThreadInternal(RTTHREADTYPE enmType, PRTTHREAD pThread);
+    HRESULT createThreadInternal(RTTHREADTYPE enmType);
     static DECLCALLBACK(int) taskHandlerThreadProc(RTTHREAD thread, void *pvUser);
 

trunk/src/VBox/Main/src-all/ThreadTask.cpp

@@ -47 +47 @@
    @endcode
  *
- * @sa createThreadWithType, createThreadWithRaceCondition
+ * @sa createThreadWithType
  */
 HRESULT ThreadTask::createThread(void)
 {
-    return createThreadInternal(RTTHREADTYPE_MAIN_WORKER, NULL /*phThread*/);
+    return createThreadInternal(RTTHREADTYPE_MAIN_WORKER);
 }
 
@@ -62 +62 @@
 HRESULT ThreadTask::createThreadWithType(RTTHREADTYPE enmType)
 {
-    return createThreadInternal(enmType, NULL /*phThread*/);
-}
-
-
-/**
- * Same ThreadTask::createThread(), except it returns a thread handle.
- *
- * If the task thread is incorrectly mananged, the caller may easily race the
- * completion and termination of the task thread!  Use with care!
- *
- * @param   phThread    Handle of the worker thread.
- */
-HRESULT ThreadTask::createThreadWithRaceCondition(PRTTHREAD phThread)
-{
-    return createThreadInternal(RTTHREADTYPE_MAIN_WORKER, phThread);
+    return createThreadInternal(enmType);
 }
 
@@ -82 +68 @@
 /**
  * Internal worker for ThreadTask::createThread,
- * ThreadTask::createThreadWithType, ThreadTask::createThreadwithRaceCondition.
+ * ThreadTask::createThreadWithType.
  *
  * @note Always consumes @a this!
  */
-HRESULT ThreadTask::createThreadInternal(RTTHREADTYPE enmType, PRTTHREAD phThread)
+HRESULT ThreadTask::createThreadInternal(RTTHREADTYPE enmType)
 {
-    RTTHREAD hThread;
-    int vrc = RTThreadCreate(&hThread,
+    int vrc = RTThreadCreate(NULL,
                              taskHandlerThreadProc,
                              (void *)this,
@@ -97 +82 @@
                              this->getTaskName().c_str());
     if (RT_SUCCESS(vrc))
-    {
-        mAsync = true;
-        if (phThread)
-            *phThread = hThread;
         return S_OK;
-    }
 
+    mAsync = false;
     delete this;
     return E_FAIL;