QPID-3858: WIP - async txns for msg publish pathway, but there are some race/thread issues to sort out.

git-svn-id: https://svn.apache.org/repos/asf/qpid/branches/asyncstore@1350745 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 106 insertions, 0 deletions

diff --git a/cpp/src/qpid/asyncStore/AtomicCounter.h b/cpp/src/qpid/asyncStore/AtomicCounter.h
new file mode 100644
index 0000000000..6987b09384
--- /dev/null
+++ b/cpp/src/qpid/asyncStore/AtomicCounter.h
@@ -0,0 +1,106 @@
+/*
+ * 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.
+ */
+
+/**
+ * \file AtomicCounter.h
+ */
+
+#ifndef qpid_asyncStore_AtomicCounter_h_
+#define qpid_asyncStore_AtomicCounter_h_
+
+#include "qpid/sys/Condition.h"
+#include "qpid/sys/Mutex.h"
+#include "qpid/sys/Time.h"
+
+namespace qpid {
+namespace asyncStore {
+
+template <class T>
+class AtomicCounter
+{
+public:
+    AtomicCounter(const T& initValue = T(0)) :
+        m_cnt(initValue),
+        m_cntMutex(),
+        m_cntCondition()
+    {}
+
+    virtual ~AtomicCounter()
+    {}
+
+    T&
+    get() const
+    {
+        qpid::sys::ScopedLock<qpid::sys::Mutex> l(m_cntMutex);
+        return m_cnt;
+    }
+
+    AtomicCounter&
+    operator++()
+    {
+        qpid::sys::ScopedLock<qpid::sys::Mutex> l(m_cntMutex);
+        ++m_cnt;
+        return *this;
+    }
+
+    AtomicCounter&
+    operator--()
+    {
+        qpid::sys::ScopedLock<qpid::sys::Mutex> l(m_cntMutex);
+        if (--m_cnt == 0) {
+            m_cntCondition.notify();
+        }
+        return *this;
+    }
+
+    bool
+    operator==(const AtomicCounter& rhs)
+    {
+        qpid::sys::ScopedLock<qpid::sys::Mutex> l1(m_cntMutex);
+        qpid::sys::ScopedLock<qpid::sys::Mutex> l2(rhs.m_cntMutex);
+        return m_cnt == rhs.m_cnt;
+    }
+
+    bool
+    operator==(const T rhs)
+    {
+        qpid::sys::ScopedLock<qpid::sys::Mutex> l(m_cntMutex);
+        return m_cnt == rhs;
+    }
+
+    void
+    waitForZero(const qpid::sys::Duration& d)
+    {
+        qpid::sys::ScopedLock<qpid::sys::Mutex> l(m_cntMutex);
+        while (m_cnt != 0) {
+            m_cntCondition.wait(m_cntMutex, qpid::sys::AbsTime(qpid::sys::AbsTime(), d));
+        }
+    }
+
+private:
+    T m_cnt;
+    mutable qpid::sys::Mutex m_cntMutex;
+    qpid::sys::Condition m_cntCondition;
+};
+
+typedef AtomicCounter<uint32_t> AsyncOpCounter;
+
+}} // namespace qpid::asyncStore
+
+#endif // qpid_asyncStore_AtomicCounter_h_