--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Framework/Deprecated/Messages/LockingEmitter.h	Sun Dec 08 11:57:46 2019 +0100
@@ -0,0 +1,89 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2019 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+#pragma once
+
+#include <Core/Enumerations.h>
+#include <Core/OrthancException.h>
+
+#include "../../Messages/IMessageEmitter.h"
+#include "../../Messages/IObservable.h"
+
+#include <Core/Enumerations.h>  // For ORTHANC_OVERRIDE
+
+#include <boost/thread/shared_mutex.hpp>
+
+namespace Deprecated
+{
+  /**
+   * This class is used when using the ThreadedOracle : since messages
+   * can be sent from multiple Oracle threads, this IMessageEmitter
+   * implementation serializes the callbacks.
+   * 
+   * The internal mutex used in Oracle messaging can also be used to 
+   * protect the application data. Thus, this class can be used as a single
+   * application-wide mutex.
+   */
+  class LockingEmitter : public OrthancStone::IMessageEmitter
+  {
+  private:
+    boost::shared_mutex        mutex_;
+    OrthancStone::IObservable  oracleObservable_;
+
+  public:
+    virtual void EmitMessage(boost::weak_ptr<OrthancStone::IObserver> observer,
+                             const OrthancStone::IMessage& message) ORTHANC_OVERRIDE;
+
+
+    class ReaderLock : public boost::noncopyable
+    {
+    private:
+      LockingEmitter& that_;
+      boost::shared_lock<boost::shared_mutex>  lock_;
+
+    public:
+      ReaderLock(LockingEmitter& that) :
+        that_(that),
+        lock_(that.mutex_)
+      {
+      }
+    };
+
+
+    class WriterLock : public boost::noncopyable
+    {
+    private:
+      LockingEmitter& that_;
+      boost::unique_lock<boost::shared_mutex>  lock_;
+
+    public:
+      WriterLock(LockingEmitter& that) :
+        that_(that),
+        lock_(that.mutex_)
+      {
+      }
+
+      OrthancStone::IObservable& GetOracleObservable()
+      {
+        return that_.oracleObservable_;
+      }
+    };
+  };
+}