'message distribution mechanism' separated from XPUB socket

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

5 files changed, 249 insertions, 132 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 3286bc4..9e362f2 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -73,6 +73,7 @@ libzmq_la_SOURCES = \
     decoder.hpp \
     device.hpp \
     devpoll.hpp \
+    dist.hpp \
     encoder.hpp \
     epoll.hpp \
     err.hpp \
@@ -141,6 +142,7 @@ libzmq_la_SOURCES = \
     decoder.cpp \
     device.cpp \
     devpoll.cpp \
+    dist.cpp \
     encoder.cpp \
     epoll.cpp \
     err.cpp \
diff --git a/src/dist.cpp b/src/dist.cpp
new file mode 100644
index 0000000..4986e81
--- /dev/null
+++ b/src/dist.cpp
@@ -0,0 +1,161 @@
+/*
+    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 "dist.hpp"
+#include "pipe.hpp"
+#include "err.hpp"
+#include "own.hpp"
+#include "msg_content.hpp"
+
+zmq::dist_t::dist_t (own_t *sink_) :
+    active (0),
+    more (false),
+    sink (sink_),
+    terminating (false)
+{
+}
+
+zmq::dist_t::~dist_t ()
+{
+    zmq_assert (pipes.empty ());
+}
+
+void zmq::dist_t::attach (writer_t *pipe_)
+{
+    pipe_->set_event_sink (this);
+
+    pipes.push_back (pipe_);
+    pipes.swap (active, pipes.size () - 1);
+    active++;
+
+    if (terminating) {
+        sink->register_term_acks (1);
+        pipe_->terminate ();
+    }
+}
+
+void zmq::dist_t::terminate ()
+{
+    zmq_assert (!terminating);
+    terminating = true;
+
+    sink->register_term_acks (pipes.size ());
+    for (pipes_t::size_type i = 0; i != pipes.size (); i++)
+        pipes [i]->terminate ();
+}
+
+void zmq::dist_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 (terminating)
+        sink->unregister_term_ack ();
+}
+
+void zmq::dist_t::activated (writer_t *pipe_)
+{
+    //  Move the pipe to the list of active pipes.
+    pipes.swap (pipes.index (pipe_), active);
+    active++;
+}
+
+int zmq::dist_t::send (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::dist_t::has_out ()
+{
+    return true;
+}
+
+bool zmq::dist_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;
+}
+
diff --git a/src/dist.hpp b/src/dist.hpp
new file mode 100644
index 0000000..4949062
--- /dev/null
+++ b/src/dist.hpp
@@ -0,0 +1,76 @@
+/*
+    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/>.
+*/
+
+#ifndef __ZMQ_DIST_HPP_INCLUDED__
+#define __ZMQ_DIST_HPP_INCLUDED__
+
+#include "array.hpp"
+#include "pipe.hpp"
+
+namespace zmq
+{
+
+    //  Class manages a set of outbound pipes. It sends each messages to
+    //  each of them.
+    class dist_t : public i_writer_events
+    {
+    public:
+
+        dist_t (class own_t *sink_);
+        ~dist_t ();
+
+        void attach (writer_t *pipe_);
+        void terminate ();
+        int send (zmq_msg_t *msg_, int flags_);
+        bool has_out ();
+
+        //  i_writer_events interface implementation.
+        void activated (writer_t *pipe_);
+        void terminated (writer_t *pipe_);
+
+    private:
+
+        //  Write the message to the pipe. Make the pipe inactive if writing
+        //  fails. In such a case false is returned.
+        bool write (class writer_t *pipe_, zmq_msg_t *msg_);
+
+        //  List of outbound pipes.
+        typedef array_t <class writer_t> pipes_t;
+        pipes_t pipes;
+
+        //  Number of active pipes. All the active pipes are located at the
+        //  beginning of the pipes array.
+        pipes_t::size_type active;
+
+        //  True if last we are in the middle of a multipart message.
+        bool more;
+
+        //  Object to send events to.
+        class own_t *sink;
+
+        //  If true, termination process is already underway.
+        bool terminating;
+
+        dist_t (const dist_t&);
+        const dist_t &operator = (const dist_t&);
+    };
+
+}
+
+#endif
diff --git a/src/xpub.cpp b/src/xpub.cpp
index 601ec23..ed9c0e5 100644
--- a/src/xpub.cpp
+++ b/src/xpub.cpp
@@ -21,13 +21,11 @@
 
 #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)
+    dist (this)
 {
     options.type = ZMQ_XPUB;
     options.requires_in = false;
@@ -36,136 +34,31 @@ zmq::xpub_t::xpub_t (class ctx_t *parent_, uint32_t tid_) :
 
 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 ();
-    }
+    dist.attach (outpipe_);
 }
 
 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 ());
+    //  Terminate the outbound pipes.
+    dist.terminate ();
 
     //  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;
+    return dist.send (msg_, flags_);
 }
 
 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;
+    return dist.has_out ();
 }
 
diff --git a/src/xpub.hpp b/src/xpub.hpp
index 1a6fe76..13baf1f 100644
--- a/src/xpub.hpp
+++ b/src/xpub.hpp
@@ -23,11 +23,12 @@
 #include "socket_base.hpp"
 #include "array.hpp"
 #include "pipe.hpp"
+#include "dist.hpp"
 
 namespace zmq
 {
 
-    class xpub_t : public socket_base_t, public i_writer_events
+    class xpub_t : public socket_base_t
     {
     public:
 
@@ -40,29 +41,13 @@ namespace zmq
         int xsend (zmq_msg_t *msg_, int flags_);
         bool xhas_out ();
 
-        //  i_writer_events interface implementation.
-        void activated (writer_t *pipe_);
-        void terminated (writer_t *pipe_);
-
     private:
 
         //  Hook into the termination process.
         void process_term (int linger_);
 
-        //  Write the message to the pipe. Make the pipe inactive if writing
-        //  fails. In such a case false is returned.
-        bool write (class writer_t *pipe_, zmq_msg_t *msg_);
-
-        //  Outbound pipes, i.e. those the socket is sending messages to.
-        typedef array_t <class writer_t> pipes_t;
-        pipes_t pipes;
-
-        //  Number of active pipes. All the active pipes are located at the
-        //  beginning of the pipes array.
-        pipes_t::size_type active;
-
-        //  True if termination process is already underway.
-        bool terminating;
+        //  Distributor of messages holding the list of outbound pipes.
+        dist_t dist;
 
         xpub_t (const xpub_t&);
         const xpub_t &operator = (const xpub_t&);