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/*
Copyright (c) 2007-2011 iMatix Corporation
Copyright (c) 2007-2011 Other contributors as noted in the AUTHORS file
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 <stddef.h>
#include "../include/zmq.h"
#include "device.hpp"
#include "socket_base.hpp"
#include "likely.hpp"
#include "err.hpp"
int zmq::device (class socket_base_t *insocket_,
class socket_base_t *outsocket_)
{
zmq_msg_t msg;
int rc = zmq_msg_init (&msg);
if (rc != 0) {
return -1;
}
int64_t more;
size_t moresz;
zmq_pollitem_t items [2];
items [0].socket = insocket_;
items [0].fd = 0;
items [0].events = ZMQ_POLLIN;
items [0].revents = 0;
items [1].socket = outsocket_;
items [1].fd = 0;
items [1].events = ZMQ_POLLIN;
items [1].revents = 0;
while (true) {
// Wait while there are either requests or replies to process.
rc = zmq_poll (&items [0], 2, -1);
if (unlikely (rc < 0)) {
return -1;
}
// The algorithm below asumes ratio of request and replies processed
// under full load to be 1:1. Although processing requests replies
// first is tempting it is suspectible to DoS attacks (overloading
// the system with unsolicited replies).
// Process a request.
if (items [0].revents & ZMQ_POLLIN) {
while (true) {
rc = insocket_->recv (&msg, 0);
if (unlikely (rc < 0)) {
return -1;
}
moresz = sizeof (more);
rc = insocket_->getsockopt (ZMQ_RCVMORE, &more, &moresz);
if (unlikely (rc < 0)) {
return -1;
}
rc = outsocket_->send (&msg, more ? ZMQ_SNDMORE : 0);
if (unlikely (rc < 0)) {
return -1;
}
if (!more)
break;
}
}
// Process a reply.
if (items [1].revents & ZMQ_POLLIN) {
while (true) {
rc = outsocket_->recv (&msg, 0);
if (unlikely (rc < 0)) {
return -1;
}
moresz = sizeof (more);
rc = outsocket_->getsockopt (ZMQ_RCVMORE, &more, &moresz);
if (unlikely (rc < 0)) {
return -1;
}
rc = insocket_->send (&msg, more ? ZMQ_SNDMORE : 0);
if (unlikely (rc < 0)) {
return -1;
}
if (!more)
break;
}
}
}
return 0;
}
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