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diff --git a/indra/llcorehttp/_refcounted.h b/indra/llcorehttp/_refcounted.h
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+++ b/indra/llcorehttp/_refcounted.h
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+/** 
+ * @file _refcounted.h
+ * @brief Atomic, thread-safe ref counting and destruction mixin class
+ *
+ * $LicenseInfo:firstyear=2012&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2012, Linden Research, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#ifndef LLCOREINT__REFCOUNTED_H_
+#define LLCOREINT__REFCOUNTED_H_
+
+
+#include <boost/thread.hpp>
+
+#include "_assert.h"
+
+
+namespace LLCoreInt
+{
+
+
+class RefCounted
+{
+private:
+	RefCounted();								// Not defined - may not be default constructed
+	void operator=(const RefCounted &);			// Not defined
+	
+public:
+	explicit RefCounted(bool const implicit) 
+		: mRefCount(implicit)
+		{}
+
+	// ref-count interface
+	void addRef() const;
+	void release() const;
+	bool isLastRef() const;
+	int getRefCount() const;
+	void noRef() const;
+
+	static const int			NOT_REF_COUNTED = -1;
+	
+protected:
+	virtual ~RefCounted();
+	virtual void destroySelf();
+
+private:
+	mutable int					mRefCount;
+	mutable boost::mutex		mRefLock;
+
+}; // end class RefCounted
+
+
+inline void RefCounted::addRef() const
+{
+	boost::mutex::scoped_lock lock(mRefLock);
+	LLINT_ASSERT(mRefCount >= 0);
+	++mRefCount;
+}
+
+
+inline void RefCounted::release() const
+{
+	int count(0);
+	{
+		// CRITICAL SECTION
+		boost::mutex::scoped_lock lock(mRefLock);
+		LLINT_ASSERT(mRefCount != NOT_REF_COUNTED);
+		LLINT_ASSERT(mRefCount > 0);
+		count = --mRefCount;
+		// CRITICAL SECTION
+	}
+
+
+	// clean ourselves up if that was the last reference
+	if (0 == count)
+	{
+		const_cast<RefCounted *>(this)->destroySelf();
+	}
+}
+
+
+inline bool RefCounted::isLastRef() const
+{
+	int count(0);
+	{
+		// CRITICAL SECTION
+		boost::mutex::scoped_lock lock(mRefLock);
+
+		LLINT_ASSERT(mRefCount != NOT_REF_COUNTED);
+		LLINT_ASSERT(mRefCount >= 1);
+		count = mRefCount;
+		// CRITICAL SECTION
+	}
+
+	return (1 == count);
+}
+
+
+inline int RefCounted::getRefCount() const
+{
+	boost::mutex::scoped_lock lock(mRefLock);
+	const int result(mRefCount);
+	return result;
+}
+
+
+inline void RefCounted::noRef() const
+{
+	boost::mutex::scoped_lock lock(mRefLock);
+	LLINT_ASSERT(mRefCount <= 1);
+	mRefCount = NOT_REF_COUNTED;
+}
+
+
+inline void RefCounted::destroySelf()
+{
+	delete this;
+}
+
+} // end namespace LLCoreInt
+
+#endif	// LLCOREINT__REFCOUNTED_H_
+