libzmq/src/tcp.cpp
Martin Hurton afe9afa2a5 Set socket buffers before establishing TCP connection
The window scale option carried in SYN segment is computed from socket's
receive buffer size. So we need to set this buffer size before calling
connect or bind.
2013-06-30 07:30:51 +02:00

152 lines
4.3 KiB
C++

/*
Copyright (c) 2007-2013 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 "ip.hpp"
#include "tcp.hpp"
#include "err.hpp"
#include "platform.hpp"
#if defined ZMQ_HAVE_WINDOWS
#include "windows.hpp"
#else
#include <fcntl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#endif
#if defined ZMQ_HAVE_OPENVMS
#include <ioctl.h>
#endif
void zmq::tune_tcp_socket (fd_t s_)
{
// Disable Nagle's algorithm. We are doing data batching on 0MQ level,
// so using Nagle wouldn't improve throughput in anyway, but it would
// hurt latency.
int nodelay = 1;
int rc = setsockopt (s_, IPPROTO_TCP, TCP_NODELAY, (char*) &nodelay,
sizeof (int));
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
#ifdef ZMQ_HAVE_OPENVMS
// Disable delayed acknowledgements as they hurt latency is serious manner.
int nodelack = 1;
rc = setsockopt (s_, IPPROTO_TCP, TCP_NODELACK, (char*) &nodelack,
sizeof (int));
errno_assert (rc != SOCKET_ERROR);
#endif
}
void zmq::set_tcp_send_buffer (fd_t sockfd_, int bufsize_)
{
const int rc = setsockopt (sockfd_, SOL_SOCKET, SO_SNDBUF,
(char*) &bufsize_, sizeof bufsize_);
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
}
void zmq::set_tcp_receive_buffer (fd_t sockfd_, int bufsize_)
{
const int rc = setsockopt (sockfd_, SOL_SOCKET, SO_RCVBUF,
(char*) &bufsize_, sizeof bufsize_);
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
}
void zmq::tune_tcp_keepalives (fd_t s_, int keepalive_, int keepalive_cnt_, int keepalive_idle_, int keepalive_intvl_)
{
// These options are used only under certain #ifdefs below.
(void)keepalive_;
(void)keepalive_cnt_;
(void)keepalive_idle_;
(void)keepalive_intvl_;
// If none of the #ifdefs apply, then s_ is unused.
(void)s_;
// Tuning TCP keep-alives if platform allows it
// All values = -1 means skip and leave it for OS
#ifdef ZMQ_HAVE_SO_KEEPALIVE
if (keepalive_ != -1) {
int rc = setsockopt (s_, SOL_SOCKET, SO_KEEPALIVE, (char*) &keepalive_, sizeof (int));
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
#ifdef ZMQ_HAVE_TCP_KEEPCNT
if (keepalive_cnt_ != -1) {
int rc = setsockopt (s_, IPPROTO_TCP, TCP_KEEPCNT, &keepalive_cnt_, sizeof (int));
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
}
#endif // ZMQ_HAVE_TCP_KEEPCNT
#ifdef ZMQ_HAVE_TCP_KEEPIDLE
if (keepalive_idle_ != -1) {
int rc = setsockopt (s_, IPPROTO_TCP, TCP_KEEPIDLE, &keepalive_idle_, sizeof (int));
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
}
#else // ZMQ_HAVE_TCP_KEEPIDLE
#ifdef ZMQ_HAVE_TCP_KEEPALIVE
if (keepalive_idle_ != -1) {
int rc = setsockopt (s_, IPPROTO_TCP, TCP_KEEPALIVE, &keepalive_idle_, sizeof (int));
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
}
#endif // ZMQ_HAVE_TCP_KEEPALIVE
#endif // ZMQ_HAVE_TCP_KEEPIDLE
#ifdef ZMQ_HAVE_TCP_KEEPINTVL
if (keepalive_intvl_ != -1) {
int rc = setsockopt (s_, IPPROTO_TCP, TCP_KEEPINTVL, &keepalive_intvl_, sizeof (int));
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
}
#endif // ZMQ_HAVE_TCP_KEEPINTVL
}
#endif // ZMQ_HAVE_SO_KEEPALIVE
}