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diff --git a/boost/log/sinks/drop_on_overflow.hpp b/boost/log/sinks/drop_on_overflow.hpp
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+/*
+ *          Copyright Andrey Semashev 2007 - 2014.
+ * Distributed under the Boost Software License, Version 1.0.
+ *    (See accompanying file LICENSE_1_0.txt or copy at
+ *          http://www.boost.org/LICENSE_1_0.txt)
+ */
+/*!
+ * \file   drop_on_overflow.hpp
+ * \author Andrey Semashev
+ * \date   04.01.2012
+ *
+ * The header contains implementation of \c drop_on_overflow strategy for handling
+ * queue overflows in bounded queues for the asynchronous sink frontend.
+ */
+
+#ifndef BOOST_LOG_SINKS_DROP_ON_OVERFLOW_HPP_INCLUDED_
+#define BOOST_LOG_SINKS_DROP_ON_OVERFLOW_HPP_INCLUDED_
+
+#include <boost/log/detail/config.hpp>
+#include <boost/log/core/record_view.hpp>
+#include <boost/log/detail/header.hpp>
+
+#ifdef BOOST_HAS_PRAGMA_ONCE
+#pragma once
+#endif
+
+namespace boost {
+
+BOOST_LOG_OPEN_NAMESPACE
+
+namespace sinks {
+
+/*!
+ * \brief Log record dropping strategy
+ *
+ * This strategy will cause log records to be discarded in case of
+ * queue overflow in bounded asynchronous sinks. It should not be used
+ * if losing log records is not acceptable.
+ */
+class drop_on_overflow
+{
+#ifndef BOOST_LOG_DOXYGEN_PASS
+public:
+    /*!
+     * This method is called by the queue when overflow is detected.
+     *
+     * \retval true Attempt to enqueue the record again.
+     * \retval false Discard the record.
+     */
+    template< typename LockT >
+    static bool on_overflow(record_view const&, LockT&)
+    {
+        return false;
+    }
+
+    /*!
+     * This method is called by the queue when there appears a free space.
+     */
+    static void on_queue_space_available()
+    {
+    }
+
+    /*!
+     * This method is called by the queue to interrupt any possible waits in \c on_overflow.
+     */
+    static void interrupt()
+    {
+    }
+#endif // BOOST_LOG_DOXYGEN_PASS
+};
+
+} // namespace sinks
+
+BOOST_LOG_CLOSE_NAMESPACE // namespace log
+
+} // namespace boost
+
+#include <boost/log/detail/footer.hpp>
+
+#endif // BOOST_LOG_SINKS_DROP_ON_OVERFLOW_HPP_INCLUDED_