XPUB and XSUB socket types added.

These are just placeholders. At the moment XPUB behaves th same
as PUB and XSUB as SUB.

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

src/xpub.cpp

@@ -0,0 +1,171 @@
+/*
+    Copyright (c) 2007-2010 iMatix Corporation
+
+    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/>.
+*/
+
+#include "../include/zmq.h"
+
+#include "xpub.hpp"
+#include "err.hpp"
+#include "msg_content.hpp"
+#include "pipe.hpp"
+
+zmq::xpub_t::xpub_t (class ctx_t *parent_, uint32_t tid_) :
+    socket_base_t (parent_, tid_),
+    active (0),
+    terminating (false)
+{
+    options.type = ZMQ_PUB;
+    options.requires_in = false;
+    options.requires_out = true;
+}
+
+zmq::xpub_t::~xpub_t ()
+{
+    zmq_assert (pipes.empty ());
+}
+
+void zmq::xpub_t::xattach_pipes (class reader_t *inpipe_,
+    class writer_t *outpipe_, const blob_t &peer_identity_)
+{
+    zmq_assert (!inpipe_);
+
+    outpipe_->set_event_sink (this);
+
+    pipes.push_back (outpipe_);
+    pipes.swap (active, pipes.size () - 1);
+    active++;
+
+    if (terminating) {
+        register_term_acks (1);
+        outpipe_->terminate ();
+    }
+}
+
+void zmq::xpub_t::process_term (int linger_)
+{
+    terminating = true;
+
+    //  Start shutdown process for all the pipes.
+    for (pipes_t::size_type i = 0; i != pipes.size (); i++)
+        pipes [i]->terminate ();
+
+    //  Wait for pipes to terminate before terminating yourself.
+    register_term_acks (pipes.size ());
+
+    //  Continue with the termination immediately.
+    socket_base_t::process_term (linger_);
+}
+
+void zmq::xpub_t::activated (writer_t *pipe_)
+{
+    //  Move the pipe to the list of active pipes.
+    pipes.swap (pipes.index (pipe_), active);
+    active++;
+}
+
+void zmq::xpub_t::terminated (writer_t *pipe_)
+{
+    //  Remove the pipe from the list; adjust number of active pipes
+    //  accordingly.
+    if (pipes.index (pipe_) < active)
+        active--;
+    pipes.erase (pipe_);
+
+    //  If we are already terminating, wait for one term ack less.
+    if (terminating)
+        unregister_term_ack ();
+}
+
+int zmq::xpub_t::xsend (zmq_msg_t *msg_, int flags_)
+{
+    //  If there are no active pipes available, simply drop the message.
+    if (active == 0) {
+        int rc = zmq_msg_close (msg_);
+        zmq_assert (rc == 0);
+        rc = zmq_msg_init (msg_);
+        zmq_assert (rc == 0);
+        return 0;
+    }
+
+    msg_content_t *content = (msg_content_t*) msg_->content;
+
+    //  For VSMs the copying is straighforward.
+    if (content == (msg_content_t*) ZMQ_VSM) {
+        for (pipes_t::size_type i = 0; i < active;)
+            if (write (pipes [i], msg_))
+                i++;
+        int rc = zmq_msg_init (msg_);
+        zmq_assert (rc == 0);
+        return 0;
+    }
+
+    //  Optimisation for the case when there's only a single pipe
+    //  to send the message to - no refcount adjustment i.e. no atomic
+    //  operations are needed.
+    if (active == 1) {
+        if (!write (pipes [0], msg_)) {
+            int rc = zmq_msg_close (msg_);
+            zmq_assert (rc == 0);
+        }
+        int rc = zmq_msg_init (msg_);
+        zmq_assert (rc == 0);
+        return 0;
+    }
+
+    //  There are at least 2 destinations for the message. That means we have
+    //  to deal with reference counting. First add N-1 references to
+    //  the content (we are holding one reference anyway, that's why -1).
+    if (msg_->flags & ZMQ_MSG_SHARED)
+        content->refcnt.add (active - 1);
+    else {
+        content->refcnt.set (active);
+        msg_->flags |= ZMQ_MSG_SHARED;
+    }
+
+    //  Push the message to all destinations.
+    for (pipes_t::size_type i = 0; i < active;) {
+        if (!write (pipes [i], msg_))
+            content->refcnt.sub (1);
+        else
+            i++;
+    }
+
+    //  Detach the original message from the data buffer.
+    int rc = zmq_msg_init (msg_);
+    zmq_assert (rc == 0);
+
+    return 0;
+}
+
+bool zmq::xpub_t::xhas_out ()
+{
+    return true;
+}
+
+bool zmq::xpub_t::write (class writer_t *pipe_, zmq_msg_t *msg_)
+{
+    if (!pipe_->write (msg_)) {
+        active--;
+        pipes.swap (pipes.index (pipe_), active);
+        return false;
+    }
+    if (!(msg_->flags & ZMQ_MSG_MORE))
+        pipe_->flush ();
+    return true;
+}
+