MCOL-513 Modify ThreadPool to have a join() method

utils/threadpool/threadpool.cpp

@@ -73,6 +73,7 @@ void ThreadPool::init()
     fStop = false;
 //     fThreadCreated = new NoOp();
     fNextFunctor = fWaitingFunctors.end();
+	fNextHandle=1;
 }
 
 void ThreadPool::setQueueSize(size_t queueSize)
@@ -115,10 +116,35 @@ void ThreadPool::wait()
     }
 }
 
-void ThreadPool::invoke(const Functor_T &threadfunc)
+void ThreadPool::join(uint64_t thrHandle)
 {
     boost::mutex::scoped_lock lock1(fMutex);
 
+    while (waitingFunctorsSize > 0)
+    {
+		Container_T::iterator iter;
+		Container_T::iterator end = fWaitingFunctors.end();
+		bool foundit = false;
+		for (iter = fWaitingFunctors.begin(); iter != end; ++iter)
+		{
+			if (iter->first == thrHandle)
+			{
+				foundit = true;
+				break;
+			}
+		}
+		if (!foundit)
+		{
+			break;
+		}
+        fThreadAvailable.wait(lock1);
+    }
+}
+
+int64_t ThreadPool::invoke(const Functor_T &threadfunc)
+{
+    boost::mutex::scoped_lock lock1(fMutex);
+	int64_t thrHandle=0;
     for(;;)
     {
 
@@ -128,7 +154,7 @@ void ThreadPool::invoke(const Functor_T &threadfunc)
             {
                 // Don't create a thread unless it's needed.  There
                 // is a thread available to service this request.
-                addFunctor(threadfunc);
+                thrHandle = addFunctor(threadfunc);
                 lock1.unlock();
                 break;
             }
@@ -138,7 +164,7 @@ void ThreadPool::invoke(const Functor_T &threadfunc)
             if ( waitingFunctorsSize < fQueueSize)
             {
                 // Don't create a thread unless you have to
-                addFunctor(threadfunc);
+                thrHandle = addFunctor(threadfunc);
                 bAdded = true;
             }
 
@@ -175,6 +201,7 @@ void ThreadPool::invoke(const Functor_T &threadfunc)
     }
 
     fNeedThread.notify_one();
+	return thrHandle;
 }
 
 void ThreadPool::beginThread() throw()
@@ -218,7 +245,7 @@ void ThreadPool::beginThread() throw()
 
 				for (i = 0; i < num; i++) {
 					try {
-	                    (*todoList[i])();
+	                    (*todoList[i]).second();
 					}
 					catch(exception &e) {
 						++fFunctorErrors;
@@ -290,24 +317,23 @@ void ThreadPool::beginThread() throw()
         catch(...)
         {
         }
-
     }
-
 }
 
-void ThreadPool::addFunctor(const Functor_T &func)
+int64_t ThreadPool::addFunctor(const Functor_T &func)
 {
     bool bAtEnd = false;
 
     if (fNextFunctor == fWaitingFunctors.end())
         bAtEnd = true;
 
-    fWaitingFunctors.push_back(func);
+    fWaitingFunctors.push_back(make_pair(fNextHandle, func));
 	waitingFunctorsSize++;
     if (bAtEnd)
     {
         --fNextFunctor;
     }
+	return fNextHandle++;
 }
 
 void ThreadPool::dump()

utils/threadpool/threadpool.h

@@ -60,6 +60,7 @@ class ThreadPool
 {
 public:
     typedef boost::function0<void> Functor_T;
+	typedef pair<int64_t, Functor_T> PoolFunction_T;
 
     /*********************************************
      *  ctor/dtor
@@ -132,7 +133,7 @@ public:
       * queueSize tasks already waiting, invoke() will block until a slot in the
       * queue comes free.
       */
-    EXPORT void invoke(const Functor_T &threadfunc);
+    EXPORT int64_t invoke(const Functor_T &threadfunc);
 
     /** @brief stop the threads
       */
@@ -142,7 +143,11 @@ public:
       */
     EXPORT void wait();
 
-    /** @brief for use in debugging
+    /** @brief Wait for a specific thread
+      */
+    EXPORT void join(uint64_t thrHandle);
+
+	/** @brief for use in debugging
       */
     EXPORT void dump();
 
@@ -155,7 +160,7 @@ private:
 
     /** @brief add a functor to the list
       */
-    void addFunctor(const Functor_T &func);
+    int64_t addFunctor(const Functor_T &func);
 
     /** @brief thread entry point
       */
@@ -191,7 +196,7 @@ private:
     size_t fMaxThreads;
     size_t fQueueSize;
 
-    typedef std::list<Functor_T> Container_T;
+    typedef std::list<PoolFunction_T> Container_T;
     Container_T fWaitingFunctors;
     Container_T::iterator fNextFunctor;
 //     Functor_T	* fThreadCreated;
@@ -206,6 +211,7 @@ private:
     long 	fGeneralErrors;
     long	fFunctorErrors;
 	uint32_t 	waitingFunctorsSize;
+	uint64_t fNextHandle;
 
 };