ZMQII-25: Implement streamed request/reply

1 files changed, 143 insertions, 0 deletions

diff --git a/src/upstream.cpp b/src/upstream.cpp
new file mode 100644
index 0000000..da202f8
--- /dev/null
+++ b/src/upstream.cpp
@@ -0,0 +1,143 @@
+/*
+    Copyright (c) 2007-2009 FastMQ Inc.
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the Lesser GNU 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
+    Lesser GNU General Public License for more details.
+
+    You should have received a copy of the Lesser GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "../bindings/c/zmq.h"
+
+#include "upstream.hpp"
+#include "err.hpp"
+#include "pipe.hpp"
+
+zmq::upstream_t::upstream_t (class app_thread_t *parent_) :
+    socket_base_t (parent_),
+    active (0),
+    current (0)
+{
+    options.requires_in = true;
+    options.requires_out = false;
+}
+
+zmq::upstream_t::~upstream_t ()
+{
+}
+
+void zmq::upstream_t::xattach_pipes (class reader_t *inpipe_,
+    class writer_t *outpipe_)
+{
+    zmq_assert (inpipe_ && !outpipe_);
+
+    pipes.push_back (inpipe_);
+    pipes.swap (active, pipes.size () - 1);
+    active++;
+}
+
+void zmq::upstream_t::xdetach_inpipe (class reader_t *pipe_)
+{
+    //  Remove the pipe from the list; adjust number of active pipes
+    //  accordingly.
+    zmq_assert (pipe_);
+    pipes_t::size_type index = pipes.index (pipe_);
+    if (index < active)
+        active--;
+    pipes.erase (index);
+}
+
+void zmq::upstream_t::xdetach_outpipe (class writer_t *pipe_)
+{
+    //  There are no outpipes, so this function shouldn't be called at all.
+    zmq_assert (false);
+}
+
+void zmq::upstream_t::xkill (class reader_t *pipe_)
+{
+    //  Move the pipe to the list of inactive pipes.
+    active--;
+    pipes.swap (pipes.index (pipe_), active);
+}
+
+void zmq::upstream_t::xrevive (class reader_t *pipe_)
+{
+    //  Move the pipe to the list of active pipes.
+    pipes.swap (pipes.index (pipe_), active);
+    active++;
+}
+
+int zmq::upstream_t::xsetsockopt (int option_, const void *optval_,
+    size_t optvallen_)
+{
+    //  No special options for this socket type.
+    errno = EINVAL;
+    return -1;
+}
+
+int zmq::upstream_t::xsend (zmq_msg_t *msg_, int flags_)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+int zmq::upstream_t::xflush ()
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+int zmq::upstream_t::xrecv (zmq_msg_t *msg_, int flags_)
+{
+    //  Deallocate old content of the message.
+    zmq_msg_close (msg_);
+
+    //  Round-robin over the pipes to get next message.
+    for (int count = active; count != 0; count--) {
+        bool fetched = pipes [current]->read (msg_);
+        current++;
+        if (current >= active)
+            current = 0;
+        if (fetched)
+            return 0;
+    }
+
+    //  No message is available. Initialise the output parameter
+    //  to be a 0-byte message.
+    zmq_msg_init (msg_);
+    errno = EAGAIN;
+    return -1;
+}
+
+bool zmq::upstream_t::xhas_in ()
+{
+    //  Note that messing with current doesn't break the fairness of fair
+    //  queueing algorithm. If there are no messages available current will
+    //  get back to its original value. Otherwise it'll point to the first
+    //  pipe holding messages, skipping only pipes with no messages available.
+    for (int count = active; count != 0; count--) {
+        if (pipes [current]->check_read ())
+            return true;
+        current++;
+        if (current >= active)
+            current = 0;
+    }
+
+    return false;
+}
+
+bool zmq::upstream_t::xhas_out ()
+{
+    return false;
+}
+