Fix CCheckQueue IsIdle (potential) race condition and remove dangerou…

…s constructors.

src/checkqueue.h

@@ -127,6 +127,9 @@ class CCheckQueue
  }
 
 public:
+ //! Mutex to ensure only one concurrent CCheckQueueControl
+ boost::mutex ControlMutex;
+
  //! Create a new check queue
  CCheckQueue(unsigned int nBatchSizeIn) : nIdle(0), nTotal(0), fAllOk(true), nTodo(0), fQuit(false), nBatchSize(nBatchSizeIn) {}
 
@@ -161,12 +164,6 @@ class CCheckQueue
  {
  }
 
- bool IsIdle()
- {
- boost::unique_lock<boost::mutex> lock(mutex);
- return (nTotal == nIdle && nTodo == 0 && fAllOk == true);
- }
-
 };
 
 /** 
@@ -177,16 +174,18 @@ template <typename T>
 class CCheckQueueControl
 {
 private:
- CCheckQueue<T>* pqueue;
+ CCheckQueue<T> * const pqueue;
  bool fDone;
 
 public:
- CCheckQueueControl(CCheckQueue<T>* pqueueIn) : pqueue(pqueueIn), fDone(false)
+ CCheckQueueControl() = delete;
+ CCheckQueueControl(const CCheckQueueControl&) = delete;
+ CCheckQueueControl& operator=(const CCheckQueueControl&) = delete;
+ explicit CCheckQueueControl(CCheckQueue<T> * const pqueueIn) : pqueue(pqueueIn), fDone(false)
  {
  // passed queue is supposed to be unused, or NULL
  if (pqueue != NULL) {
- bool isIdle = pqueue->IsIdle();
- assert(isIdle);
+ ENTER_CRITICAL_SECTION(pqueue->ControlMutex);
  }
  }
 
@@ -209,6 +208,9 @@ class CCheckQueueControl
  {
  if (!fDone)
  Wait();
+ if (pqueue != NULL) {
+ LEAVE_CRITICAL_SECTION(pqueue->ControlMutex);
+ }
  }
 };