initial version of req/rep sockets

1 files changed, 206 insertions, 0 deletions

diff --git a/src/req.cpp b/src/req.cpp
new file mode 100644
index 0000000..05629df
--- /dev/null
+++ b/src/req.cpp
@@ -0,0 +1,206 @@
+/*
+    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 "req.hpp"
+#include "err.hpp"
+#include "pipe.hpp"
+
+zmq::req_t::req_t (class app_thread_t *parent_) :
+    socket_base_t (parent_, ZMQ_REQ),
+    current (0),
+    waiting_for_reply (false),
+    reply_pipe_active (false),
+    reply_pipe (NULL)
+{
+}
+
+zmq::req_t::~req_t ()
+{
+}
+
+bool zmq::req_t::xrequires_in ()
+{
+    return true;
+}
+
+bool zmq::req_t::xrequires_out ()
+{
+    return true;
+}
+
+void zmq::req_t::xattach_pipes (class reader_t *inpipe_,
+    class writer_t *outpipe_)
+{
+    zmq_assert (inpipe_ && outpipe_);
+    zmq_assert (in_pipes.size () == out_pipes.size ());
+
+    in_pipes.push_back (inpipe_);
+    out_pipes.push_back (outpipe_);
+}
+
+void zmq::req_t::xdetach_inpipe (class reader_t *pipe_)
+{
+    zmq_assert (pipe_);
+    zmq_assert (in_pipes.size () == out_pipes.size ());
+
+    //  TODO: The pipe we are awaiting the reply from is detached. What now?
+    //  Return ECONNRESET from subsequent recv?
+    if (waiting_for_reply && pipe_ == reply_pipe) {
+        zmq_assert (false);
+    }
+
+    in_pipes_t::size_type index = in_pipes.index (pipe_);
+
+    //  If corresponding outpipe is still in place simply nullify the pointer
+    //  to the inpipe.
+    if (out_pipes [index]) {
+        in_pipes [index] = NULL;
+        return;
+    }
+
+    //  Now both inpipe and outpipe are detached. Remove them from the lists.
+    in_pipes.erase (index);
+    out_pipes.erase (index);
+}
+
+void zmq::req_t::xdetach_outpipe (class writer_t *pipe_)
+{
+    zmq_assert (pipe_);
+    zmq_assert (in_pipes.size () == out_pipes.size ());
+
+    out_pipes_t::size_type index = out_pipes.index (pipe_);
+
+    //  If corresponding inpipe is still in place simply nullify the pointer
+    //  to the outpipe.
+    if (in_pipes [index]) {
+        out_pipes [index] = NULL;
+        return;
+    }
+
+    //  Now both inpipe and outpipe are detached. Remove them from the lists.
+    in_pipes.erase (index);
+    out_pipes.erase (index);
+}
+
+void zmq::req_t::xkill (class reader_t *pipe_)
+{
+    zmq_assert (pipe_ == reply_pipe);
+
+    reply_pipe_active = false;
+}
+
+void zmq::req_t::xrevive (class reader_t *pipe_)
+{
+    //  TODO: Actually, misbehaving peer can cause this kind of thing.
+    //  Handle it decently, presumably kill the offending connection.
+    zmq_assert (pipe_ == reply_pipe);
+
+    reply_pipe_active = true;
+}
+
+int zmq::req_t::xsetsockopt (int option_, const void *optval_,
+    size_t optvallen_)
+{
+    errno = EINVAL;
+    return -1;
+}
+
+int zmq::req_t::xsend (struct zmq_msg_t *msg_, int flags_)
+{
+    //  If we've sent a request and we still haven't got the reply,
+    //  we can't send another request.
+    if (waiting_for_reply) {
+        errno = EFAULT;
+        return -1;
+    }
+
+    if (out_pipes.empty ()) {
+        errno = EFAULT;
+        return -1;
+    }
+
+    current++;
+    if (current >= out_pipes.size ())
+        current = 0;
+
+    //  TODO: Infinite loop can result here. Integrate the algorithm with
+    //  the active pipes list (i.e. pipe pair that has one pipe missing is
+    //  considered to be inactive.
+    while (!in_pipes [current] || !out_pipes [current]) {
+        current++;
+        if (current >= out_pipes.size ())
+            current = 0;
+    }
+
+    //  TODO: Implement this once queue limits are in-place.
+    zmq_assert (out_pipes [current]->check_write (zmq_msg_size (msg_)));
+
+    //  Push message to the selected pipe.
+    out_pipes [current]->write (msg_);
+    out_pipes [current]->flush ();
+
+    waiting_for_reply = true;
+    reply_pipe = in_pipes [current];
+
+    //  We can safely assume that the reply pipe is active as the last time
+    //  we've used it we've read the reply and haven't tried to read from it
+    //  anymore.
+    reply_pipe_active = true;
+
+    //  Detach the message from the data buffer.
+    int rc = zmq_msg_init (msg_);
+    zmq_assert (rc == 0);
+
+    return 0;
+}
+
+int zmq::req_t::xflush ()
+{
+    errno = EFAULT;
+    return -1;
+}
+
+int zmq::req_t::xrecv (struct zmq_msg_t *msg_, int flags_)
+{
+    //  Deallocate old content of the message.
+    zmq_msg_close (msg_);
+
+    //  If request wasn't send, we can't wait for reply.
+    if (!waiting_for_reply) {
+        zmq_msg_init (msg_);
+        errno = EFAULT;
+        return -1;
+    }
+
+    //  Get the reply from the reply pipe.
+    if (!reply_pipe_active || !reply_pipe->read (msg_)) {
+        zmq_msg_init (msg_);
+        errno = EAGAIN;
+        return -1;
+    }
+
+    waiting_for_reply = false;
+    reply_pipe = NULL;
+
+    return 0;
+}
+
+