libzmq/src/stream.hpp

/*
    Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file

    This file is part of libzmq, the ZeroMQ core engine in C++.

    libzmq is free software; you can redistribute it and/or modify it under
    the terms of the GNU Lesser General Public License (LGPL) as published
    by the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    As a special exception, the Contributors give you permission to link
    this library with independent modules to produce an executable,
    regardless of the license terms of these independent modules, and to
    copy and distribute the resulting executable under terms of your choice,
    provided that you also meet, for each linked independent module, the
    terms and conditions of the license of that module. An independent
    module is a module which is not derived from or based on this library.
    If you modify this library, you must extend this exception to your
    version of the library.

    libzmq 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_STREAM_HPP_INCLUDED__
#define __ZMQ_STREAM_HPP_INCLUDED__

#include <map>

#include "router.hpp"

namespace zmq
{

    class ctx_t;
    class pipe_t;

    class stream_t :
        public socket_base_t
    {
    public:

        stream_t (zmq::ctx_t *parent_, uint32_t tid_, int sid);
        ~stream_t ();

        //  Overrides of functions from socket_base_t.
        void xattach_pipe (zmq::pipe_t *pipe_, bool subscribe_to_all_);
        int xsend (zmq::msg_t *msg_);
        int xrecv (zmq::msg_t *msg_);
        bool xhas_in ();
        bool xhas_out ();
        void xread_activated (zmq::pipe_t *pipe_);
        void xwrite_activated (zmq::pipe_t *pipe_);
        void xpipe_terminated (zmq::pipe_t *pipe_);
        int xsetsockopt (int option_, const void *optval_, size_t optvallen_); 
    private:
        //  Generate peer's id and update lookup map
        void identify_peer (pipe_t *pipe_);

        //  Fair queueing object for inbound pipes.
        fq_t fq;

        //  True iff there is a message held in the pre-fetch buffer.
        bool prefetched;

        //  If true, the receiver got the message part with
        //  the peer's identity.
        bool identity_sent;

        //  Holds the prefetched identity.
        msg_t prefetched_id;

        //  Holds the prefetched message.
        msg_t prefetched_msg;

        struct outpipe_t
        {
            zmq::pipe_t *pipe;
            bool active;
        };

        //  Outbound pipes indexed by the peer IDs.
        typedef std::map <blob_t, outpipe_t> outpipes_t;
        outpipes_t outpipes;

        //  The pipe we are currently writing to.
        zmq::pipe_t *current_out;

        //  If true, more outgoing message parts are expected.
        bool more_out;

        //  Routing IDs are generated. It's a simple increment and wrap-over
        //  algorithm. This value is the next ID to use (if not used already).
        uint32_t next_rid;

        stream_t (const stream_t&);
        const stream_t &operator = (const stream_t&);
    };

}

#endif