Refactored common impl into gssapi_mechanism_base.

E.g., both client and server need to produce and process GSSAPI tokens.

src/gssapi_mechanism_base.hpp

@@ -0,0 +1,48 @@
+/*
+    Copyright (c) 2007-2013 Contributors as noted in the AUTHORS file
+
+    This file is part of 0MQ.
+
+    0MQ 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; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ 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 program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __ZMQ_GSSAPI_MECHANISM_BASE_HPP_INCLUDED__
+#define __ZMQ_GSSAPI_MECHANISM_BASE_HPP_INCLUDED__
+
+namespace zmq
+{
+
+    class msg_t;
+
+    // Both gssapi_server and gssapi_client need to produce and process
+    // GSSAPI tokens.  Common implementation is captured here.
+
+    class gssapi_mechanism_base_t
+    {
+    public:
+        gssapi_mechanism_base_t ();
+        virtual ~gssapi_mechanism_base_t () = 0;
+
+    protected:
+
+        //  True iff we are awaiting another GSSAPI token.
+        bool gss_continue_needed;
+
+        int produce_token (msg_t *msg_) const;
+        int process_token (msg_t *msg_);
+    };
+
+}
+
+#endif