client/BlockingQueue.h, sys/ConcurrentQueue.h: merged to sys/BlockingQueue.h

 - updated all users 	  

qpid/Exception.h: Removed unimplemented clone() function.


git-svn-id: https://svn.apache.org/repos/asf/incubator/qpid/trunk/qpid@589857 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 127 insertions, 0 deletions

diff --git a/cpp/src/qpid/sys/BlockingQueue.h b/cpp/src/qpid/sys/BlockingQueue.h
new file mode 100644
index 0000000000..65196dbd9c
--- /dev/null
+++ b/cpp/src/qpid/sys/BlockingQueue.h
@@ -0,0 +1,127 @@
+#ifndef QPID_SYS_BLOCKINGQUEUE_H
+#define QPID_SYS_BLOCKINGQUEUE_H
+
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+#include "Waitable.h"
+
+#include <queue>
+
+namespace qpid {
+namespace sys {
+
+struct QueueClosed {};
+
+template <class T>
+class BlockingQueue
+{
+    sys::Waitable lock;
+    std::queue<T> queue;
+    bool closed;
+
+public:
+    BlockingQueue() : closed(false) {}
+    ~BlockingQueue() { close(); }
+
+    /** Block until there is a value to pop */
+    T pop()
+    {
+        Waitable::ScopedLock l(lock);
+        if (!queueWait()) throw QueueClosed();
+        return popInternal();
+    }
+
+    /** Non-blocking pop. If there is a value set outValue and return
+     * true, else return false;
+     */
+    bool tryPop(T& outValue) {
+        Waitable::ScopedLock l(lock);
+        if (queue.empty()) return false;
+        outValue = popInternal();
+        return true;
+    }
+
+    /** Non-blocking pop. If there is a value return it, else return
+     * valueIfEmpty.
+     */
+    T tryPop(const T& valueIfEmpty=T()) {
+        T result=valueIfEmpty;
+        tryPop(result);
+        return result;
+    }
+
+    /** Push a value onto the queue */
+    void push(const T& t)
+    {
+        Waitable::ScopedLock l(lock);
+        queue.push(t);
+        queueNotify(0);
+    }
+
+    /**
+     * Close the queue. Throws QueueClosed in threads waiting in pop().
+     * Blocks till all waiting threads have been notified.
+     */ 
+    void close()
+    {
+        Waitable::ScopedLock l(lock);
+        if (!closed) {
+            closed = true;
+            lock.notifyAll();
+            lock.waitWaiters(); // Ensure no threads are still waiting.
+        }
+    }
+
+    /** Open a closed queue. */
+    void open() {
+        Waitable::ScopedLock l(lock);
+        closed=false;
+    }
+
+  private:
+
+    void queueNotify(size_t ignore) {
+        if (!queue.empty() && lock.hasWaiters()>ignore)
+            lock.notify();      // Notify another waiter.
+    }
+
+    bool queueWait() {
+        Waitable::ScopedWait w(lock);
+        while (!closed && queue.empty())
+            lock.wait();
+        return !queue.empty();
+    }
+
+    T popInternal() {
+        T t=queue.front();
+        queue.pop();
+        queueNotify(1);
+        return t;
+    }
+    
+};
+
+}}
+
+
+
+#endif  /*!QPID_SYS_BLOCKINGQUEUE_H*/