Added boost header

test/external/boost/signals2/shared_connection_block.hpp

@@ -0,0 +1,64 @@
+// Boost.Signals2 library
+
+// Copyright Frank Mori Hess 2007-2008.
+// Use, modification and
+// distribution is subject to 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)
+
+// For more information, see http://www.boost.org
+
+#ifndef BOOST_SIGNALS2_SHARED_CONNECTION_BLOCK_HPP
+#define BOOST_SIGNALS2_SHARED_CONNECTION_BLOCK_HPP
+
+#include <boost/shared_ptr.hpp>
+#include <boost/signals2/connection.hpp>
+#include <boost/weak_ptr.hpp>
+
+namespace boost
+{
+  namespace signals2
+  {
+    class shared_connection_block
+    {
+    public:
+      shared_connection_block(const signals2::connection &conn = signals2::connection(),
+        bool initially_blocked = true):
+        _weak_connection_body(conn._weak_connection_body)
+      {
+        if(initially_blocked) block();
+      }
+      void block()
+      {
+        if(blocking()) return;
+        boost::shared_ptr<detail::connection_body_base> connection_body(_weak_connection_body.lock());
+        if(connection_body == 0)
+        {
+          // Make _blocker non-empty so the blocking() method still returns the correct value
+          // after the connection has expired.
+          _blocker.reset(static_cast<int*>(0));
+          return;
+        }
+        _blocker = connection_body->get_blocker();
+      }
+      void unblock()
+      {
+        _blocker.reset();
+      }
+      bool blocking() const
+      {
+        shared_ptr<void> empty;
+        return _blocker < empty || empty < _blocker;
+      }
+      signals2::connection connection() const
+      {
+        return signals2::connection(_weak_connection_body);
+      }
+    private:
+      boost::weak_ptr<detail::connection_body_base> _weak_connection_body;
+      shared_ptr<void> _blocker;
+    };
+  }
+} // end namespace boost
+
+#endif // BOOST_SIGNALS2_SHARED_CONNECTION_BLOCK_HPP