Added QThreadPool::waitForDone(int msecs)

Merge-request: 641
Reviewed-by: Olivier Goffart <olivier.goffart@nokia.com>
Reviewed-by: Morten Sorvig
Task-number: QTBUG-2695

4 files changed, 60 insertions, 4 deletions

diff --git a/src/corelib/concurrent/qthreadpool.cpp b/src/corelib/concurrent/qthreadpool.cpp
index 9e4189e..f25a494 100644
--- a/src/corelib/concurrent/qthreadpool.cpp
+++ b/src/corelib/concurrent/qthreadpool.cpp
@@ -41,6 +41,7 @@
 
 #include "qthreadpool.h"
 #include "qthreadpool_p.h"
+#include "qelapsedtimer.h"
 
 #ifndef QT_NO_THREAD
 
@@ -288,11 +289,21 @@ void QThreadPoolPrivate::reset()
     isExiting = false;
 }
 
-void QThreadPoolPrivate::waitForDone()
+bool QThreadPoolPrivate::waitForDone(int msecs)
 {
     QMutexLocker locker(&mutex);
-    while (!(queue.isEmpty() && activeThreads == 0))
-        noActiveThreads.wait(locker.mutex());
+    if (msecs < 0) {
+        while (!(queue.isEmpty() && activeThreads == 0))
+            noActiveThreads.wait(locker.mutex());
+    } else {
+        QElapsedTimer timer;
+        timer.start();
+        int t;
+        while (!(queue.isEmpty() && activeThreads == 0) && 
+               ((t = msecs - timer.elapsed()) > 0))
+            noActiveThreads.wait(locker.mutex(), t);
+    }
+    return queue.isEmpty() && activeThreads == 0;
 }
 
 /*! \internal
@@ -617,6 +628,23 @@ void QThreadPool::waitForDone()
     d->reset();
 }
 
+/*!
+    \overload waitForDone()
+    \since 4.8
+
+    Waits up to \a msecs milliseconds for all threads to exit and removes all 
+    threads from the thread pool. Returns true if all threads were removed; 
+    otherwise it returns false.
+*/
+bool QThreadPool::waitForDone(int msecs)
+{
+    Q_D(QThreadPool);
+    bool rc = d->waitForDone(msecs);
+    if (rc)
+      d->reset();
+    return rc;
+}
+
 QT_END_NAMESPACE
 
 #endif
diff --git a/src/corelib/concurrent/qthreadpool.h b/src/corelib/concurrent/qthreadpool.h
index cc1e059..0bd1884 100644
--- a/src/corelib/concurrent/qthreadpool.h
+++ b/src/corelib/concurrent/qthreadpool.h
@@ -85,6 +85,7 @@ public:
     void releaseThread();
 
     void waitForDone();
+    bool waitForDone(int msecs);
 };
 
 QT_END_NAMESPACE
diff --git a/src/corelib/concurrent/qthreadpool_p.h b/src/corelib/concurrent/qthreadpool_p.h
index 8a2cf98..3d2d6be 100644
--- a/src/corelib/concurrent/qthreadpool_p.h
+++ b/src/corelib/concurrent/qthreadpool_p.h
@@ -82,7 +82,7 @@ public:
 
     void startThread(QRunnable *runnable = 0);
     void reset();
-    void waitForDone();
+    bool waitForDone(int msecs = -1);
     bool startFrontRunnable();
     void stealRunnable(QRunnable *);
 
diff --git a/tests/auto/qthreadpool/tst_qthreadpool.cpp b/tests/auto/qthreadpool/tst_qthreadpool.cpp
index 7c8b410..cd6070f 100644
--- a/tests/auto/qthreadpool/tst_qthreadpool.cpp
+++ b/tests/auto/qthreadpool/tst_qthreadpool.cpp
@@ -89,6 +89,7 @@ private slots:
     void tryStartPeakThreadCount();
     void tryStartCount();
     void waitForDone();
+    void waitForDoneTimeout();
     void destroyingWaitsForTasksToFinish();
     void stressTest();
 };
@@ -774,6 +775,32 @@ void tst_QThreadPool::waitForDone()
     }
 }
 
+void tst_QThreadPool::waitForDoneTimeout()
+{
+    class BlockedTask : public QRunnable
+    {
+    public:
+      QMutex mutex;
+      BlockedTask() { setAutoDelete(false); }
+      
+      void run()
+        {
+          mutex.lock();
+          mutex.unlock();
+          QTest::qSleep(50);
+        }
+    };
+
+    QThreadPool threadPool;
+
+    BlockedTask *task = new BlockedTask;
+    task->mutex.lock();
+    threadPool.start(task);
+    QVERIFY(!threadPool.waitForDone(100));
+    task->mutex.unlock();
+    QVERIFY(threadPool.waitForDone(400));
+}
+
 void tst_QThreadPool::destroyingWaitsForTasksToFinish()
 {
     QTime total, pass;