zmq: add support for TIPC transport

A ZeroMQ application can opt for TIPC based sockets
using the TIPC port name format:
zmq_bind(sb, "tipc://{type,lower,upper}");
zmq_connect(sc, "tipc://{type,inst}");

'type' is the service ID, and 'lower/upper' can be
used for service partitioning or basic load
balancing.

ZeroMQ TIPC transport requires a kernel >= 3.8
(nonblocking connect support for TIPC).

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>

src/tipc_connecter.hpp

@@ -0,0 +1,127 @@
+/*
+    Copyright (c) 2013 Ericsson AB
+
+    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 __TIPC_CONNECTER_HPP_INCLUDED__
+#define __TIPC_CONNECTER_HPP_INCLUDED__
+
+#include "platform.hpp"
+
+#if defined ZMQ_HAVE_LINUX
+
+#include "fd.hpp"
+#include "own.hpp"
+#include "stdint.hpp"
+#include "io_object.hpp"
+
+namespace zmq
+{
+
+    class io_thread_t;
+    class session_base_t;
+    struct address_t;
+
+    class tipc_connecter_t : public own_t, public io_object_t
+    {
+    public:
+
+        //  If 'delayed_start' is true connecter first waits for a while,
+        //  then starts connection process.
+        tipc_connecter_t (zmq::io_thread_t *io_thread_,
+            zmq::session_base_t *session_, const options_t &options_,
+            const address_t *addr_, bool delayed_start_);
+        ~tipc_connecter_t ();
+
+    private:
+
+        //  ID of the timer used to delay the reconnection.
+        enum {reconnect_timer_id = 1};
+
+        //  Handlers for incoming commands.
+        void process_plug ();
+        void process_term (int linger_);
+
+        //  Handlers for I/O events.
+        void in_event ();
+        void out_event ();
+        void timer_event (int id_);
+
+        //  Internal function to start the actual connection establishment.
+        void start_connecting ();
+
+        //  Internal function to add a reconnect timer
+        void add_reconnect_timer();
+
+        //  Close the connecting socket.
+        void close ();
+
+        //  Get the file descriptor of newly created connection. Returns
+        //  retired_fd if the connection was unsuccessfull.
+        fd_t connect ();
+
+        //  Address to connect to. Owned by session_base_t.
+        const address_t *addr;
+
+        //  Underlying socket.
+        fd_t s;
+
+        //  Handle corresponding to the listening socket.
+        handle_t handle;
+
+        //  If true file descriptor is registered with the poller and 'handle'
+        //  contains valid value.
+        bool handle_valid;
+
+        //  If true, connecter is waiting a while before trying to connect.
+        const bool delayed_start;
+
+        //  True iff a timer has been started.
+        bool timer_started;
+
+        //  Reference to the session we belong to.
+        zmq::session_base_t *session;
+
+        //  Current reconnect ivl, updated for backoff strategy
+        int current_reconnect_ivl;
+
+        // String representation of endpoint to connect to
+        std::string endpoint;
+
+        // Socket
+        zmq::socket_base_t *socket;
+
+        //  Internal function to return a reconnect backoff delay.
+        //  Will modify the current_reconnect_ivl used for next call
+        //  Returns the currently used interval
+        int get_new_reconnect_ivl ();
+
+        //  Open IPC connecting socket. Returns -1 in case of error,
+        //  0 if connect was successfull immediately. Returns -1 with
+        //  EAGAIN errno if async connect was launched.
+        int open ();
+
+        tipc_connecter_t (const tipc_connecter_t&);
+        const tipc_connecter_t &operator = (const tipc_connecter_t&);
+    };
+
+}
+
+#endif
+
+#endif
+