--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Core/MultiThreading/ReaderWriterLock.cpp	Tue Apr 22 13:36:51 2014 +0200
@@ -0,0 +1,122 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2014 Medical Physics Department, CHU of Liege,
+ * Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders of this
+ * program give permission to link the code of its release with the
+ * OpenSSL project's "OpenSSL" library (or with modified versions of it
+ * that use the same license as the "OpenSSL" library), and distribute
+ * the linked executables. You must obey the GNU General Public License
+ * in all respects for all of the code used other than "OpenSSL". If you
+ * modify file(s) with this exception, you may extend this exception to
+ * your version of the file(s), but you are not obligated to do so. If
+ * you do not wish to do so, delete this exception statement from your
+ * version. If you delete this exception statement from all source files
+ * in the program, then also delete it here.
+ * 
+ * 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "ReaderWriterLock.h"
+
+#include <boost/thread/shared_mutex.hpp>
+
+namespace Orthanc
+{
+  namespace
+  {
+    // Anonymous namespace to avoid clashes between compilation
+    // modules.
+
+    class ReaderLockable : public ILockable
+    {
+    private:
+      boost::shared_mutex& lock_;
+
+    public:
+      ReaderLockable(boost::shared_mutex& lock) : lock_(lock)
+      {
+      }
+
+      virtual void Lock()
+      {
+        lock_.lock_shared();
+      }
+
+      virtual void Unlock()
+      {
+        lock_.unlock_shared();        
+      }
+    };
+
+
+    class WriterLockable : public ILockable
+    {
+    private:
+      boost::shared_mutex& lock_;
+
+    public:
+      WriterLockable(boost::shared_mutex& lock) : lock_(lock)
+      {
+      }
+
+      virtual void Lock()
+      {
+        lock_.lock();
+      }
+
+      virtual void Unlock()
+      {
+        lock_.unlock();        
+      }
+    };
+  }
+
+  struct ReaderWriterLock::PImpl
+  {
+    boost::shared_mutex lock_;
+    ReaderLockable reader_;
+    WriterLockable writer_;
+
+    PImpl() : reader_(lock_), writer_(lock_)
+    {
+    }
+  };
+
+
+  ReaderWriterLock::ReaderWriterLock()
+  {
+    pimpl_ = new PImpl;
+  }
+
+
+  ReaderWriterLock::~ReaderWriterLock()
+  {
+    delete pimpl_;
+  }
+
+
+  ILockable&  ReaderWriterLock::ForReader()
+  {
+    return pimpl_->reader_;
+  }
+
+
+  ILockable&  ReaderWriterLock::ForWriter()
+  {
+    return pimpl_->writer_;
+  }
+}