Added boost header

test/external/boost/signals2/mutex.hpp

@@ -0,0 +1,38 @@
+//
+//  boost/signals2/mutex.hpp - header-only mutex
+//
+//  Copyright (c) 2002, 2003 Peter Dimov and Multi Media Ltd.
+//  Copyright (c) 2008 Frank Mori Hess
+//
+// 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)
+//
+//  boost::signals2::mutex is a modification of
+//  boost::detail::lightweight_mutex to follow the newer Lockable
+//  concept of Boost.Thread.
+//
+
+#ifndef BOOST_SIGNALS2_MUTEX_HPP
+#define BOOST_SIGNALS2_MUTEX_HPP
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+#include <boost/config.hpp>
+
+#if !defined(BOOST_HAS_THREADS)
+# include <boost/signals2/detail/lwm_nop.hpp>
+#elif defined(BOOST_HAS_PTHREADS)
+#  include <boost/signals2/detail/lwm_pthreads.hpp>
+#elif defined(BOOST_HAS_WINTHREADS)
+#  include <boost/signals2/detail/lwm_win32_cs.hpp>
+#else
+// Use #define BOOST_DISABLE_THREADS to avoid the error
+#  error Unrecognized threading platform
+#endif
+
+#endif // #ifndef BOOST_SIGNALS2_MUTEX_HPP